Irish apple cake folds diced apples into butter batter beneath oat streusel, with a separately cooked custard sauce.
Cake eggs, sauce yolks and their milk portions are distinct. Use a deep 9 x 3 inch springform on a supporting sheet, and cook the yolk sauce before serving or chilling it.
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Why the Streusel Stays Cold While Batter Is Mixed
Cold streusel butter stays in crumbs while the cake batter is prepared. Scattering that mixture over the apples keeps the oat topping distinct from the soft fruit-filled crumb.
Warm milk is whisked gradually into yolks and sugar before gentle cooking. Constant stirring thickens the sauce without relying on refrigeration to cook the eggs.
Ingredients for Irish Apple Cake
Cake
- 1/2 cup unsalted butter (Softened)
- 1/2 cup granulated sugar
- 2 teaspoons vanilla extract
- 2 large eggs
- 1 1/4 cups all-purpose flour
- 1 teaspoon baking powder
- 1 teaspoon ground cinnamon
- 1/4 teaspoon salt
- 3 tablespoons pasteurized milk
- 3 cups peeled diced tart apples
- 1 teaspoon butter (Pan)
Streusel
- 3/4 cup all-purpose flour
- 1/4 cup rolled oats
- 1/2 cup granulated sugar
- 1/4 teaspoon salt
- 6 tablespoons unsalted butter (Cold)
Custard
- 3/4 cup pasteurized whole milk
- 1/8 teaspoon salt
- 3 large egg yolks
- 1/4 cup granulated sugar
- 1 teaspoon vanilla extract
Apple measure: Use three cups peeled diced tart apples.
Eggs and milk: Two whole eggs and three tablespoons milk belong to cake; three yolks and three-quarter cup milk make the sauce.
Butter portions: Keep softened cake butter, cold streusel butter and the pan teaspoon separate.
How to Make Irish Apple Cake
- Prepare cold streusel. Heat oven to 350°F and line and grease the deep springform on a supporting sheet. Mix streusel flour, oats, sugar and salt, rub in cold butter until crumbly and refrigerate.
- Mix and bake cake. Cream cake butter and sugar, add cake vanilla and eggs one at a time. Whisk cake dry ingredients and fold in with three tablespoons milk, then apples. Spread in pan, scatter cold streusel and bake fifty to sixty-five minutes until the center is set and a tester away from fruit shows baked crumbs.
- Cool and cook sauce. Cool cake fifteen minutes in the pan, release carefully and continue on a rack. Warm custard milk and salt. Whisk yolks and sauce sugar, gradually add warm milk, return to low heat and stir constantly until at least 160°F and spoon-coating, without boiling.
- Finish twelve portions. Remove sauce from heat and stir in its vanilla. Serve promptly or transfer to a shallow container and chill promptly. Cut twelve cake slices and share the sauce alongside.
Serving Irish Apple Cake
Serve the sauce separately so each slice receives its share. For an apple cake with a frosting layer, compare apple pecan spice cake.
For apples baked beneath a cake then inverted, see caramel apple upside down cake.
Storage and Make-Ahead Notes
Refrigerate cake and cooked custard separately, covered at 40°F or below, and use within three days. Shallow-chill sauce promptly if not serving it immediately.
Keep waiting custard cold; reheat the needed portion to 165°F while stirring gently. Add it to slices near eating rather than storing the whole cake soaked in sauce.
Tips for Irish Apple Cake
- Keep streusel cold: Refrigerate crumbs while the cake bowl is mixed.
- Separate milk measures: Cake uses tablespoons; sauce uses its own three-quarter cup.
- Temper yolks gradually: Whisk in warm milk in stages before low-heat cooking.
- Avoid a hard boil: Stir custard constantly and use its temperature and coating checks.
Irish Apple Cake FAQs
Do the three yolks go in cake?
They belong to the custard; cake uses two whole eggs.
How is milk divided?
Three tablespoons in cake and three-quarter cup in sauce.
Can custard set safely without cooking?
Cook it to at least 160°F and spoon-coating before serving or chilling.
When is streusel added?
Scatter the chilled crumbs over the apple batter before baking.
What is the yield?
Twelve slices with the separately prepared sauce divided alongside.
Food handling reference: FDA safe food handling guidance.
Irish Apple Cake with Oat Streusel and Custard Sauce
Equipment
- 9 x 3 inch springform
- Supporting baking sheet
- Mixer
- Saucepan
- Whisk
- Instant read thermometer
Ingredients
Cake
- 1/2 cup unsalted butter Softened
- 1/2 cup granulated sugar
- 2 teaspoons vanilla extract
- 2 large eggs
- 1 1/4 cups all-purpose flour
- 1 teaspoon baking powder
- 1 teaspoon ground cinnamon
- 1/4 teaspoon salt
- 3 tablespoons pasteurized milk
- 3 cups peeled diced tart apples
- 1 teaspoon butter Pan
Streusel
- 3/4 cup all-purpose flour
- 1/4 cup rolled oats
- 1/2 cup granulated sugar
- 1/4 teaspoon salt
- 6 tablespoons unsalted butter Cold
Custard
- 3/4 cup pasteurized whole milk
- 1/8 teaspoon salt
- 3 large egg yolks
- 1/4 cup granulated sugar
- 1 teaspoon vanilla extract
Instructions
- Heat oven to 350°F and line and grease the deep springform on a supporting sheet. Mix streusel flour, oats, sugar and salt, rub in cold butter until crumbly and refrigerate.
- Cream cake butter and sugar, add cake vanilla and eggs one at a time. Whisk cake dry ingredients and fold in with three tablespoons milk, then apples. Spread in pan, scatter cold streusel and bake fifty to sixty-five minutes until the center is set and a tester away from fruit shows baked crumbs.
- Cool cake fifteen minutes in the pan, release carefully and continue on a rack. Warm custard milk and salt. Whisk yolks and sauce sugar, gradually add warm milk, return to low heat and stir constantly until at least 160°F and spoon-coating, without boiling.
- Remove sauce from heat and stir in its vanilla. Serve promptly or transfer to a shallow container and chill promptly. Cut twelve cake slices and share the sauce alongside.
