01 - Line a 12-cup muffin tin with paper liners or arrange silicone molds on a flat baking sheet.
02 - Combine graham cracker crumbs, sugar, and melted butter in a bowl and stir until evenly moistened. Press approximately 1 tablespoon of the mixture firmly into the bottom of each liner. Refrigerate while preparing the filling.
03 - Beat the cream cheese in a large bowl until completely smooth. Add powdered sugar, vanilla extract, lemon zest, and ground lavender, then mix until fully incorporated and creamy.
04 - Whip the heavy cream in a separate bowl to stiff peaks. Gently fold the whipped cream into the cream cheese mixture in two additions, maintaining as much air as possible for a light, fluffy texture.
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.
06 - Cover the muffin tin with plastic wrap and refrigerate for at least 4 hours or overnight until the filling is firm and set.
07 - Combine blackberries, sugar, and lemon juice in a small saucepan over medium heat. Cook for about 5 minutes, stirring and gently mashing the berries, until the mixture becomes syrupy. Remove from heat and let cool completely.
08 - Spoon the cooled blackberry sauce over each mini cheesecake. Garnish with a fresh blackberry or a small sprig of lavender if desired, then serve immediately.