Strawberry and blackberry icebox cake

Instructions

1. Line a 9-by-5-inch loaf pan with plastic wrap, letting the ends hang over the long sides of the pan by several inches.
2. Using an electric mixer, in a large bowl, beat the yogurt, cream cheese, and sugar until fluffy, about 3 minutes. Beat in the lemon zest and vanilla. Gently fold in the whipped topping.
3. Line the bottom of the prepared pan with 3 graham cracker squares; top evenly with about ¾ cup of the yogurt mixture, then ⅓ cup each strawberries and blackberries. Repeat the layers 3 more times. Top with the remaining graham crackers.
4. Cover the top of the cake with the overhanging plastic wrap. Gently press down on the top and pat the edges to form an even shape. Refrigerate until the graham crackers soften, at least 8 hours or up to 1 day.
5. Just before serving, uncover the cake and invert it onto a platter; remove the plastic wrap. Using a long serrated knife, cut the cake into 8 slices. Dust the slices lightly with cinnamon and garnish with mint sprigs (if using). Serve with more berries.
6. Serving size: 1 slice