Whisk together the flour, baking powder, and salt. Set aside.

Using an electric mixer on medium speed, beat the butter and sugar until light and fluffy. Add the egg and mix well. Mix in the vanilla.

Reduce mixer speed to low. Gradually add the flour mixture, mixing just until combined.

Spread the batter in the bottom of the prepared pan. Bake 18 to 22 minutes, or until the edges are browned, and a pick inserted into the center comes out clean. Allow the cake to cool completely.

Cut 4 rounds to fit serving glasses and cut the remaining cake into cubes. Alternatively, cut all of the cake into cubes.

Using an electric mixer on medium speed, beat the cream cheese, sugar, and lemon until thoroughly combined and smooth.

Place the cream in a large, cold mixing bowl. Using an electric mixer with a whisk attachment, beat at medium-high speed until the cream begins to thicken.

Continue beating until you can lift the whisk out of the whipped cream and a peak that curves downward forms in the cream. This should take 4 to 5 minutes.

Transfer about 1/4 of the whipped cream to the cream cheese mixture. Mix just until combined. Then gently fold in the remaining whipped cream, mixing just until combined

Beginning with the cake rounds (or about half the cubed cake if you cubed all of it) and continuing with cheesecake and berries, layer the components in serving glasses until full. Top with sweetened whipped cream and more berries. Chill at least 4 hours or overnight.