01 - Line a 12-cup muffin tin with paper liners or arrange silicone molds on a flat tray.
02 - Combine the graham cracker crumbs, granulated sugar, and melted butter in a bowl, stirring until the mixture resembles wet sand. Press approximately 1 tablespoon of the mixture firmly into the bottom of each liner. Place the tin in the refrigerator to chill while preparing the filling.
03 - Beat the softened cream cheese in a large bowl using an electric mixer until completely smooth. Add the powdered sugar, vanilla extract, lemon zest, and ground lavender, then mix until fully incorporated and no lumps remain.
04 - In a separate bowl, whip the heavy cream to stiff peaks. Gently fold the whipped cream into the cream cheese mixture in two additions, maintaining as much air as possible, until the filling is smooth and fluffy.
05 - Spoon or pipe the cheesecake filling evenly over the chilled crusts, dividing it among all 12 cups. Smooth the tops with a small spatula or the back of a spoon.
06 - Cover the muffin tin tightly and refrigerate for at least 4 hours, or until the filling is firm and set throughout.
07 - Combine the fresh blackberries, granulated sugar, and lemon juice in a small saucepan. Cook over medium heat, stirring frequently and gently mashing the berries with the back of a spoon, until the mixture becomes syrupy, about 5 minutes. Remove from heat and let cool completely.
08 - Spoon the cooled blackberry sauce over each mini cheesecake. Garnish with a sprig of fresh lavender or a whole blackberry, if desired. Serve chilled.