Heat the oven to 400°F. Have ready a 12-cup standard muffin tin.

To make the topping, stir all of the ingredients in a small bowl with a fork, until the mixture holds together when squeezed, and place in the refrigerator.

To make the crust, whisk the dry ingredients in a large mixing bowl.

Heat the butter and milk in the microwave in a heat-proof glass measuring cup on high until the butter melts.

Add the butter/milk mixture to the dry ingredients and stir with a fork until the mixture holds together when squeezed.

Knead the dough a few times in the bowl with your hands.

Divide the dough into 12 small balls, about 35 grams each, and evenly press the dough onto the bottom and up the sides of each cavity using your fingers.

Try to keep the dough warm prior to shaping it in each cavity, but covering it with a dishtowel. The dough is easiest to work with when warm.

To prepare the berries, whisk the sugar, cornstarch, and salt in the same bowl in which you prepared the crust. No need to clean it.

Stir in the berries and lemon juice with a flexible spatula.

Scoop about one heaping tablespoon of berries and add it to one of the cavities. Repeat with the remaining berries.

Top each mini pie with about a tablespoon of the crumble.

Place the tin in the oven and bake until the edges of the crust are golden brown and the berries are bubbling, about 30 minutes.

Bring the pies to room temperature before serving in order to ensure the filling is set.