Preheat the oven to 350°F (177°C). Grease an 8-inch cake pan or 9-inch cake pan, line with parchment paper rounds, then grease the parchment paper. Parchment paper helps the cakes seamlessly release from the pans. (If it’s helpful, see this parchment paper rounds for cakes video & post.)

Sift the cake flour, sugar, baking powder, and salt in the bowl of a stand mixer. (Or if using a handheld mixer, any large mixing bowl.) Add the butter, vanilla, and 1/4 cup milk. Mix on medium speed until the dry ingredients are moistened, about 1 minute. Stop the mixer and scrape down the sides and up the bottom of the bowl.

Whisk the remaining milk, the egg, and oil together. With the mixer running on medium speed, add the egg mixture in 2 additions, mixing for about 15 seconds between. Stop the mixer and scrape down the sides and up the bottom of the bowl if needed, then mix for about 15 more seconds or until batter is completely combined. Avoid over-mixing. Some small lumps are OK.

Pour batter into cake pan. Bake for around 20-22 minutes or until the cake is baked through. To test for doneness, insert a toothpick into the center of the cake. If it comes out clean, it’s done. Cool cake completely in the pan set on a wire rack.

When the cake is just about cooled, mix the sliced strawberries, jam, and sugar together. Let it sit at room temperature or in the refrigerator so the strawberries release some of their juices.

Using a hand mixer or a stand mixer fitted with a whisk attachment, whip the heavy cream, sugar, and vanilla extract on medium-high speed until medium peaks form, about 3-4 minutes. Medium peaks are between loose peaks and stiff peaks and are the perfect consistency for topping on cakes.

Place the cooled cake on your serving plate or cake stand. Pile whipped cream on top, then gently spread it out to the edges. Top with strawberries.

Slice and serve cake immediately or refrigerate for up to 4 hours before serving. Cover and store leftovers in the refrigerator for up to 3 days.