01 - Line a 12-cup muffin tin with paper liners or arrange silicone molds on a baking sheet.
02 - In a mixing bowl, combine the graham cracker crumbs, granulated sugar, and melted butter, 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 set while preparing the filling.
03 - In a large bowl, beat the softened cream cheese with an electric mixer until completely smooth and free of lumps. Add the powdered sugar, vanilla extract, lemon zest, and ground lavender, then mix on medium speed until fully incorporated and creamy.
04 - In a separate chilled bowl, whip the heavy cream to stiff peaks using a whisk or electric mixer. Gently fold the whipped cream into the cream cheese mixture in three additions, preserving as much air as possible, until the filling is smooth, light, and fluffy.
05 - Spoon or pipe the 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 with plastic wrap 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 a spoon, until the mixture reduces to a syrupy consistency, 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, then serve immediately.