Preheat Oven: Heat oven to 325°F (162°C) and line a cupcake pan with liners.
Prepare Crust: Mix graham cracker crumbs, sugar, and butter. Press into cupcake liners and bake for 5 minutes. Cool.
Make Cheesecake Filling: Beat cream cheese, sugar, and flour. Add sour cream, lavender extract, and vanilla. Beat in eggs one at a time. Add violet gel color if desired.
Fill & Bake: Spoon the filling into liners. Bake at 300°F (148°C) for 18-20 minutes. Let cool in the oven with the door cracked before refrigerating for 3+ hours.
Prepare Blackberry Topping: Puree blackberries and cook with sugar and cornstarch until thickened. Cool before spreading on cheesecakes.
Whip Cream & Decorate: Whip cream, powdered sugar, and vanilla until peaks form. Pipe onto cheesecakes and garnish with fresh blackberries.