1 cup all-purpose flour
6 Tbs. chilled butter
3 cups whole frozen blackberries – or 1½ cup fresh
1 Tbs. cornstarch
1 Tbs. water
1/3 cup sugar
Step 1: Make dough.
Use a pastry cutter to combine butter into flour until the mixture resembles wet sand.
Add cold water in a little at a time and knead until a pie crust forms.
Use your fingers to push pie dough evenly into a buttered and floured muffin tin (3-in. diameter and 1-in. deep).
Prick each tart crust with a fork to allow the steam to pass through.
Bake at 350F until the crust is cooked, about 15 minutes.
Step 2: Make Filling.
If you are using frozen blackberries, thaw them. (The 3 cups frozen become 1½ cups when thawed. Save the juice.)
Crush half the blackberries in a saucepan and add all the juice that drained out (about ¼ cup juice) and the sugar.
Cook on high heat while stirring for about 5 minutes. The mixture should thicken.
In a small bowl, stir together cornstarch and water until there are no clumps and add to saucepan.
Cook over high heat for about 3-4 minutes, stirring, until the mixture thickens to a jam consistency. If needed, add a little more cornstarch. Add in the remaining whole blackberries. Remove from heat.
Step 3: Assemble.
Pour the blackberry filling into the cooled baked muffin tin and refrigerate until firm, about 1 ½ hrs. Makes 6 tarts.