Preheat oven to 350°F.

In a medium bowl, whisk flour, baking powder, and salt until combined. Set aside.

Using a stand mixer fitted with the paddle attachment or a hand mixer, beat sugar, oil, eggs, egg whites, and extracts until combined. Add the sour cream and beat until combined. Add half of the flour mixture, beating until just combined. While still beating, slowly add milk, then the remaining flour mixture. Scrape the sides and bottom of the bowl as needed. Be careful not to overmix.

Line three 8-inch cake pans with parchment paper and grease the pans. Evenly divide the batter between the three pans. Tap/gently drop the pans on the countertop a couple times to remove any air bubbles.

Bake for 18-22 minutes, until a toothpick inserted into the center comes out clean. If necessary, rotate the pans once during bake time to ensure even browning. Place the pans on a rack to cool completely.

Combine the strawberries and jam and set aside. You'll need about 3 cups total.

Place the cream cheese, powdered sugar, and vanilla extract in a large mixing bowl. Using a stand mixer with a whisk attachment or hand mixer, beat the mixture on medium speed until smooth. While the mixer is still whipping, slowly pour the heavy cream down the side of the bowl. Stop and scrape the bottom and sides of the bowl periodically. Increase the speed to high and continue whipping until the cream can hold a stiff peak.

Place one layer of cake on a platter. Top with one-third of the frosting, then top with about 1¼ cups of strawberries. Place another layer of cake on top and repeat. For the third/top layer of cake, top with remaining whipped cream frosting, then place the remaining strawberries in the center. Decorate the outside with whole strawberries, if desired.