01 - Preheat the oven to 350°F (175°C). Line a 12-cup muffin tin with paper liners or lightly grease each cavity.
02 - In a large mixing bowl, whisk together the melted butter, light brown sugar, and granulated sugar until the mixture is smooth.
03 - Blend in the egg and vanilla extract until the batter is thoroughly combined.
04 - Add all-purpose flour, baking powder, and salt. Stir until the dry ingredients are just incorporated, taking care not to overmix.
05 - Divide the blondie batter evenly among the prepared muffin cups, using approximately 2 tablespoons per cup.
06 - In a medium bowl, mix the ricotta cheese, honey, and lemon zest until completely smooth.
07 - Drop about 1 tablespoon of ricotta mixture onto the center of each portion of blondie batter.
08 - Place a few mixed berries on top of each cup, gently pressing them into the ricotta layer.
09 - Bake in the preheated oven for 22 to 25 minutes, until the edges are golden and the centers are just set.
10 - Allow blondie cups to cool in the muffin tin for 10 minutes, then transfer to a wire rack to cool completely.