Preheat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

In a mixing bowl, combine flour, sugar, baking powder, and salt.

Add softened butter, milk, eggs, and vanilla extract. Beat with an electric mixer until smooth.

Divide the batter evenly between the prepared pans.

Bake for 25 minutes or until a toothpick inserted in the center comes out clean.

Let the cakes cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.

In a mixing bowl, whip the heavy cream until soft peaks form. Gradually add powdered sugar and vanilla, continuing to whip until stiff peaks form.

Place one cake layer on a cake stand. Spread a layer of whipped cream frosting on top.

Add a layer of sliced strawberries, blueberries, and raspberries.

Top with the second cake layer and frost the top and sides with the remaining whipped cream.

Decorate with additional fresh fruits and mint leaves.

Slice and serve at your garden party!