01 - Line a standard 12-cup muffin tin with paper liners, or alternatively arrange 12 silicone molds on a flat baking sheet.
02 - In a medium bowl, combine the graham cracker crumbs, granulated sugar, and melted butter, stirring until the mixture resembles wet sand and holds together when pinched. Distribute approximately 1 tablespoon of the crumb mixture into each liner and press firmly into an even layer using the back of a spoon or the bottom of a small glass. Place the tin in the refrigerator to set while preparing the filling.
03 - In a large mixing bowl, beat the softened cream cheese with an electric mixer on medium speed until completely smooth and free of lumps, about 1 to 2 minutes. Add the powdered sugar, vanilla extract, lemon zest, and ground lavender, then continue mixing until all ingredients are fully incorporated and the mixture is creamy.
04 - In a separate chilled bowl, whip the heavy cream to stiff peaks using an electric mixer or a whisk. Using a spatula, gently fold the whipped cream into the cream cheese mixture in three additions, being careful to maintain as much air as possible, until the filling is smooth, light, and uniformly combined.
05 - Spoon or pipe the filling evenly over the chilled crusts, dividing it among all 12 cups. Smooth the tops with a small offset spatula or the back of a spoon.
06 - Cover the muffin tin tightly with plastic wrap and refrigerate for a minimum of 4 hours, or preferably overnight, until the cheesecakes are firmly set.
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 reduces to a syrupy consistency, about 5 minutes. Remove from heat and allow the compote to cool completely to room temperature.
08 - Once the cheesecakes are fully set and the compote has cooled, spoon the blackberry sauce generously over each mini cheesecake. Garnish with a sprig of fresh lavender or a single whole blackberry, if desired, and serve chilled.