Creamy Oven Baked Onions Irish Style

Creamy oven baked onions make a delicious side dish, especially when served with roast dinners, such as Thanksgiving turkey dinner or a Sunday roast beef or chicken dinner.

This creamed onion recipe is a popular Irish side dish. It’s an old fashioned onion casserole that’s not too difficult to make. It can cook in the oven right alongside a roast for dinner.

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Irish Style Baked Onions

This is one of my favorite recipes involving onions. Creamy and sweet deliciousness in every bite, and so good with roast turkey or chicken. I also love to serve them with roast pork or lamb and of course with a good steak.

They're delicious served with roast potatoes or sweet potato casserole.

If you have ever wondered what interesting things you can do with onions, then this recipe might be just for you.

Oven baked onions in cream take this humble, everyday vegetable to the next level of tastiness.

Now I married a man who won’t touch an onion. I made this recipe and licked my lips. I tried to tempt him to take a bite. I was half hoping his feelings toward onions had changed over time.

Of course, he wouldn’t even look twice at the dish, not to mind take a bite. All my efforts were in vain, but I sure enjoyed this side made with heavy cream.

Can you bake onions?

Onions are a wonderful vegetable for baking. Have you ever wondered why onions become sweet when cooked?

The answer lies in the onion's composition. They contain a lot of large molecules of natural sugars. As the onions bake and heat in the oven over an extended period of time, the natural sugars found in the onion start to caramelize.

This process intensifies the sugars in the onions. The result is a wonderfully flavorful, savory yet sweet, combination.

Onions also contain sulphur which causes you to cry when chopping them. The heating and baking process helps reduce the sulphur content, making them far less pungent and more palatable.

This is why onions change so much when you cook them. There is an amazing intensification of sugars and a reduction of bitter sulphur concentration.

What is the best type of onion for baking?

The best onions for baking are yellow onions. White onions work great too.

The regular onions sold in Irish supermarkets work great.

Vidalia onions in America are my onion of choice for this casserole. They’re named after the town in Georgia where they are primarily grown.

Now the Vidalia is a type of yellow onion, but oh are they extra sweet. They have a much higher concentration of natural sugars compared to other types of yellow onions. Most onions contain 5% sugars while a Vidalia boasts a whopping 12% of sugars. Now that’s a sweet onion.

They also have a low sulfur content. They are only grown in 20 counties in Georgia, where the soil has a low sulphur content.

I hope you’ll enjoy this Irish style vidalia onion casserole.

Should you leave the skin on when roasting onions?

You can roast onions whole and in their skins. We'll explore how to cook onions in the oven using this method on another day. Today let’s focus on baked creamy onions.

For these creamy onions, I peel them, but do leave them whole.

Oven baked creamed onions can be served as unbroken onion halves straight from the casserole dish. Two to three onion halves create a serving.

They’re topped with the delicious creamy sauce created during the cooking process.

Are the onions washed before cooking?

There is no need to wash the onions before cooking them in this Irish onion casserole recipe.

The first step for this onion side dish involves simmering the whole peeled onions in salted water. This helps remove and reduce the amount of sulphur in the onions.

Then the onions are transferred to a greased casserole, topped with cream and baked in the oven to caramelize them.

Because these onions are par boiled before baking, they do not take too long to finish cooking in the oven.

The baking time is less than 30 minutes and the total cooking time is less than an hour.

Cream or Cheese Sauce for Irish Style Baked Onions?

Many baked onion recieps use parmesan cheese to top the halved onions in the casserole. This Irish style recipe calls for a cream sauce made with heavy cream and no cheese.

The higher the fat content in the cream the more delicious the sauce will be.

If you prefer parmesan creamed onions then simply mix about ½ cup of grated parmesan cheese into the heavy whipping cream before pouring it over the onions.

Some people like to add some toppings to this casserole before the end of cooking time. Toasted breadcrumbs or a little grated parmesan can add a lovely layer to this onion casserole. Many people top it with grated white cheddar cheese.

For me I prefer to keep it simple, and just add the cream sauce.

Ingredients for Baked Onions

Here's a list of what you'll need. Check the printable recipe at the end of this post for exact quantities.

• small onions (use similarly sized onions)
• sea salt
• water to cover the onions in the saucepan
• butter or olive oil to grease the baking dish
• fresh thyme sprigs (kept intact)
• heavy whipping cream
• freshly ground pepper
• freshly chopped parsley (to garnish)

Fresh thyme is my herb of choice for this dish. You could substitute one or two bay leaves for the thyme. Rosemary is another great choice.

But feel free to experiment. You can transform this dish by using fresh rosemary instead of the thyme.

Pearl onions can be substituted for the large onions, but reduce the simmering time to 10 minutes prior to baking. Also reduce the time in the oven by 10 minutes for these smaller onions.

Equipment for Creamy Baked Onions

Here's the kitchen equipment you'll need for this dish.

• 2-quart baking dish (9 x 13 casserole dish or baking pan)
• large saucepan

Directions for Creamy Onions

Preheat the oven to 350 degrees Fahrenheit. Use the butter to grease the baking dish.

Peel the onions and remove the tops and tails using a sharp knife. The roots of the onions must be removed before cooking.

Add water to a large saucepan and lightly salt the water. Make sure you don't use a small saucepan.

The onions need to be completely surrounded by water to help remove their sulphur and bitterness.

I do not recommend making this recipe with onion slices. Pre-boiling sliced onions will remove too many juices and flavor for this recipe to be a success.

Bring to the boil. Add the onions and bring back to boiling point. Reduce the heat and allow the onions to simmer for 20 minutes until tender.

If you like to add extra flavor to these onions, par boil them in chicken broth or chicken stock instead of water.

Remove the onions from the heat and drain. Allow to cool slightly before cutting the onions in half.

Arrange the onion halves flat side down or cut side down in the greased baking dish. You can grease the pan with butter, or you can use one or two tablespoons extra-virgin olive oil.

Place the thyme sprigs in different places between the onions in the dish. Be sure to scatter tyhem around the large baking dish.

Pour the cream over the onions and top with a light dusting of freshly ground black pepper.

You can add a tablespoon of the onion water to the cream if you wish, but I usually skip this step.

Bake in the oven uncovered for 20 to 25 minutes until bubbling and turning slightly golden brown.

Remove the thyme sprigs. Garnish with fresh parsley and serve warm from the dish.

And there you have it! A simple, inexpensive yet delicious side dish that's sure to impress.

This dish is pefect for entertaining, Thanksgiving dinner, or for holiday get togethers.

Recipe Card for Creamy Baked Onions

Here's a short video showing these cooking techniques and recipe.

Here's the printable recipe if you'd like to add this Irish specialty to your files.

Happy cooking from my Irish kitchen to yours. Here are some other side dishes you might enjoy...

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