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How to Cook Oatmeal in a Slow Cooker

In Oliver Twist by Charles Dickens, the protagonist, Oliver asks the cook at the workhouse for more gruel “Please, Sir, I want some more.” The gruel that they are referring to is oatmeal. In the time of Dickens, workhouse, and poor laws, oatmeal was regarded as a (fitting) food for the poor.

Gruel is a thinner version of porridge. Porridge (alternate spellings, porage, parritch) is made by boiling oatmeal, or other legumes in water or milk, or both, then serving in a bowl while still hot.

Thankfully we have progressed a tremendous amount since the days of Dickens, Oliver Twist, and gruel. Now we want to eat nutritious and delicious oatmeal in the morning. We know that oats and oatmeal products are essential to include in your diet because of their high water-soluble fiber content. The daily intake of one bowl of oatmeal can lower your blood cholesterol, due to its soluble fiber content

You don’t even have to cook it? You can use your slow cooker or rice cooker to cook oatmeal over night, to be ready and then enjoyed in the morning, evening, at night or any other time you want some.

Currently, oatmeal is viewed primarily as a breakfast cereal or food. However, you can also use it as an ingredient in main dishes, side dishes, breads, cakes, cookies and other desserts.

What is oatmeal? There are many different forms of edible oats and oatmeal. It is important to know the differences before selecting oatmeal products for your recipes.

Types of oats and oatmeal

♦ Oat Groats: Groats are the inner portion of the oat kernel. These are oats that have been cleaned, toasted, hulled, and cleaned again. They require a long cooking time and even then are chewy. If you pound or roll them you can reduce the cooking time. Oat groats are sweet and have a moist, chewy texture;

♦ Rolled Oats: These are oat groats that have been steamed, pressed with a roller then dried. These oats are also known as old-fashioned oats. The cooking time is approximately 15 minutes;

♦ Oatmeal: This is a meal made from rolled or ground oat grouts, steel-cut oats, crushed oats, or rolled oats. It is also known as oatmeal cereal. In Ireland, it is called stirabout. Rolled oats that are sold as oatmeal may have had the tough bran removed. They can be processed, lightly baked or pressure-cooked. Oatmeal can be further processed into a coarse powder, which, when cooked, becomes a thick broth;

♦ Oat Flakes: These are whole oat kernels that have been steamed, flattened through rollers, and flaked, to retain nutrients. As quick cooking oats (see below), they are used in cereals, muesli, and in baking. Thick-rolled oats are large whole flakes, thin-rolled oats are smaller, fragmented flakes. Oat flakes that are basically rolled whole oats without further processing can be cooked and eaten as old-fashioned oatmeal. However, processed rolled oats (sold as quick or instant oatmeal, see below) tend to absorb water, thus cooking faster;

♦ Instant Oatmeal: This is oatmeal that is pre-cooked then dried. Really it is processed rolled oats. Instant oatmeal may also have an additional ingredient, flavor additives. You cannot substitute instant oatmeal for rolled or quick-cooking oats;

♦ Quick-Cooking Oats: These are rolled oats cut into smaller pieces and rolled thinner (i.e., oat flakes). As a result, the cooking time is about 5 minutes. The thinness of the flake determines whether oats are classified as regular or quick-cooking oats. In short, quick-cooking oats have thinner flakes than regular oats;

♦ Oat Flour: This is flour made from ground oat groats. It does not contain gluten; that is, it is gluten-free. Oat flour contains natural antioxidants that can extend the shelf-life of baked goods;

♦ Oat Bran: This is the outer coating of the oat grain. It is very high in fiber;

♦ Steel-Cut Oats: These oats are unrolled oats. They are whole grain groats cut into only 2 or 3 pieces by steel rather than rolled. They are golden in color and resemble small pieces of rice. Traditionally found in Ireland, Scotland, and the Isle of Man, steel-cut oats are also known as Coarse-Cut Oats, Pinhead Oats, or Irish Oats. (Often confused with Scottish Oats or Scottish Oatmeal. Scottish Oats are steamed steel-cut oats that are then ground by stones into an oat meal.)

Both of the following recipes require Rolled Oats.


• In both these recipes Do Not Use Quick Cooking Oats!

• Both these methods will NOT work with Instant Oats!

My personal favorite is steel-cut oats. These oats when cooked have a nutty flavor and a chewy texture. When cooked stove top, these oats take longer to prepare, typically 15-30 minutes to simmer (much less if pre-soaked).

I always pre-soak them before using these oats in any recipe. They are also delicious as a savory side dish.

Steel-cut oats may also have a lower glycaemic index than instant oatmeal (42 vs. 66, respectively). Consuming steel-cut oats will cause your insulin level to spike less, probably because of a higher proportion of complex carbohydrate.

Each of the following recipes makes 4 to 5 servings.

♥ In the Slow Cooker or Crock Pot


♦ 2 cups (500 ml.) oats;

♦ 4 cups (1 litre) water or milk;

♦¼ teaspoon (1.25 ml.) salt


♦ Combine all the ingredients (oats, water/milk, salt) in your slow cooker or crock pot;

♦ Stir;

♦ Cover and cook for 7-8 hours on low heat;

♦ Go to bed;

♦ Wake up and Enjoy

♥ In the Rice Cooker


♦ 2 cups (500 ml.) of oats;

♦ 2 cups (500 ml.) of water or milk;

♦¼ teaspoon (1.25 ml.) salt


♦ Place all ingredients (oats, water/milk, and salt) in Rice Cooker;

♦ Turn on;

♦ Go to bed;

♦ Wake up and Enjoy.

There are variations to both of these recipes:

You can add (at the start of the cooking process)

• ½ cup (125 ml.) of honey;

• dried fruit (e.g., apricots, apple, raspberries, blackberries, blueberries, and so forth). NOTE: In the Rice Cooker recipe, when adding dried fruit (e.g., apricots, apple, raspberries, blackberries, blueberries and so forth), it is suggested that the water content in the recipe be increased by ½ cup (125 ml.):

• 1/2 to 1 teaspoon (2.5 to 5.0 ml.) ground cinnamon, ginger or nutmeg. NOTE: The amount of cinnamon, ginger or nutmeg provided here is based on my personal preferences.

• for a change, try savory oatmeal. At the beginning of the cooking process, add and cook 2 minced garlic cloves and 1 teaspoon (5.0 ml) minced rosemary. Don’t care for the taste of rosemary, try thyme, tarragon or lavender;

• for sweet oatmeal in the morning, add 2 tablespoons (30.0 ml.) raisins, currants or chopped dates,1 cinnamon stick or 1/2 teaspoon (2.5 ml.) of ground cinnamon. Then either 1 teaspoon (5.0 ml.) orange zest, 1/2 teaspoon (2.5 ml.) orange extract, or 1 teaspoon (2.5 ml.) lemon juice;

• or sweeten your oatmeal with brown sugar, maple syrup, or corn syrup;

• or banana slices, honey and cinnamon.

(References available upon request.)