Step 1

Preheat the oven to 350 F. Add the cubed butter to a 9 x 13 inch baking dish or pan. Place the dish in the oven for a few minutes until the butter is melted.

Step 2

Meanwhile, in a medium bowl, combine the flour, granulated sugar, baking powder, and salt. Add the milk and vanilla extract and stir until smooth.

Step 3

Pour the batter evenly over the melted butter in the pan (do not stir!). The melted butter will rise up over the batter.

Step 4

Toss the peach slices and blueberries with the lemon juice and spread them evenly over the batter (again, do not stir).

Step 5

Sprinkle the brown sugar evenly over the top and and bake 40-50 minutes until the top is golden brown. Allow the cobbler to cool a few minutes before serving.