Warm slice of oatmeal cake with caramelized coconut-cinnamon frosting and optional pecans beside a cup of coffee.

Oatmeal Cake with Broiled Cinnamon Frosting

Oats: Use old-fashioned rolled oats for the intended texture. Let them soften for the full 20 minutes and cool until warm before adding them to the batter.
Mixing: Once the flour is added, mix only until no dry streaks remain. Excess mixing can make the crumb dense instead of tender.
Pan and Broiler: Use a manufacturer-approved broiler-safe 9-inch square baking pan. Do not place ordinary glass bakeware beneath the broiler. Keep the cake in its baking pan for topping, broiling, and serving.
Nuts: For an optional variation, stir ½ cup chopped pecans or walnuts into the frosting before spreading it over the cake.
Make Ahead: The finished cake can be made one day ahead. Let it cool completely before covering.
Storage and Reheating: Store covered at room temperature for up to 3 days or refrigerate for up to 5 days. Freeze tightly wrapped for up to 2 months; the topping will soften after thawing. Warm an individual slice briefly before serving if desired.
Serving Suggestions: Serve slightly warm with coffee or Russian Spiced Tea .

Name: Oatmeal Cake with Broiled Cinnamon Frosting
Prep time: 20 min
Cook time: 55 min
Total time: 105 min
Yield: 12 slices
Ingredients: 1 cup old-fashioned oats; 1 ¼ cups boiling water; 1 ½ cups all-purpose flour; 1 teaspoon baking soda; ½ teaspoon salt; ¾ teaspoon cinnamon; ¼ teaspoon nutmeg; ½ cup unsalted butter; 1 cup granulated sugar; 1 cup brown sugar; 1 teaspoon vanilla extract; 2 large eggs; ¼ cup unsalted butter; ½ cup brown sugar; ¾ cup sweetened shredded coconut; 3 tablespoons heavy cream or whole milk; 1 teaspoon vanilla extract; ½ teaspoon cinnamon

Softened oats keep this warmly spiced cake tender and moist. Its coconut-cinnamon frosting bubbles under the broiler into a sweet, toasted top that's especially good while still a little gooey.

By Betty Lou Gardner1 hr 45 minUpdated 2026-08-25

This Oatmeal Cake with Broiled Cinnamon Frosting is soft, moist, and warmly spiced with tender oats throughout and a bubbling coconut-cinnamon topping caramelized under the broiler! Rich without feeling too heavy, it’s the kind of old-fashioned cake that tastes especially good slightly warm with coffee in the afternoon.

Betty Lou Gardner in a family archival photograph

Granny’s Kitchen Notes

From Betty Lou Gardner

I always think oatmeal cake smells comforting before it even comes out of the oven. Sometimes I add pecans to the frosting because the nuts toast beautifully once the topping bubbles under the broiler, and I like this best while the frosting is still just a little gooey on top.