Combine flour, sugar, salt, and butter in bowl. Mix with hands, squeezing through fingers until forms large moist crumbs that hold together. (you can use a food processor, for this step)

Press dough into individual mini round tart pan with a removable bottom. (this recipe made 4 small tarts with a thick crust) Make sure to use flour dusted finger tips. Cover bottom and sides of each pan. Freeze until firm, about 15 minutes. Use a fork to poke small holes across bottom of crust. Bake at 375 F until golden brown. Transfer to cooling rack for 15 minutes.

In a medium saucepan add 1 ⅔ cups berries and ¼ cup water to a boil. Reduce heat and stir until berries soften.

Mix cornstarch and 2 Tbsp water in a bowl, then add to berry mixture. Next, stir in lemon zest , juice, sugar, and salt. Increase to a boil once again, then simmer while stirring until thickened.

Spoon berry mixture onto cooled tart shells. Placing remaining uncooked berries on top for decoration. Lightly sprinkle lemon zest ion top. Refrigerate until set.