Preheat oven to 350° F. For tartlet pans, place Mason jar lids, ring side up, on a sheet pan.
Mix all dough ingredients in a food processor until crumbly. Squeeze mixture in your hands to form a ball. If mixture is too dry to hold together, add 1-2 tbsp. of water. Divide dough into 6 equal portions.
Press dough into the bottom and up the sides of each tartlet pan. Bake for 10 minutes, until firm. Remove from oven and allow to cool completely.
Carefully remove tartlet shells from pans and spoon 1/4 cup yogurt into each. Top with fresh berries and serve