Preheat oven to 350 degrees. Line a 9x13 pan with parchment paper hanging over the sides. In a large bowl, mix together flour, sugar, baking powder, and salt.
Next mix in eggs, vanilla extract, almond extract, milk, sour cream, and oil. Pour in prepared pan and bake for 30 minutes or until a toothpick comes out clean when poked in the center. Let cool for 10 minutes then remove from the pan and cool on rack.
In a large skillet cook 5 cups berries, sugar, lemon zest and juice, and 1 tablespoon vanilla until the berries break down and release juices, about 20 minutes.
Make the topping by whipping the heavy cream on high until it starts to thicken. Then mix in powdered sugar and vanilla. Continue to whip to stiff peaks.
To assemble, place cake on a tray and poke holes in the cake with the back of a plastic serving spoon. Spread berries with juice over the cake. Top with whipped cream, remaining 1 cup of thawed frozen berries and sliced strawberries.