Step 1: Prepare the Crust

1. Preheat oven to 325°F (163°C) and line a muffin tin with cupcake liners.
2. In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter, mixing until the texture resembles wet sand.
3. Press about 1 tablespoon of the mixture into each liner.
4. Bake for 5 minutes, then set aside to cool.

Step 2: Make the Raspberry Swirl

1. In a small saucepan over medium heat, combine raspberries, sugar, and lemon juice.
2. Cook for 3-5 minutes, stirring occasionally, until the berries break down.
3. Strain through a fine-mesh sieve to remove seeds. Set aside to cool.

Step 3: Prepare the Cheesecake Filling

1. In a large bowl, beat softened cream cheese until smooth.
2. Add sugar, vanilla extract, lemon zest, and lemon juice, mixing until combined.
3. Beat in egg and sour cream, mixing just until smooth. Do not overmix.

Step 4: Assemble the Cheesecake Cups

1. Spoon about 2 tablespoons of cheesecake filling over the crusts.
2. Add small dollops of raspberry sauce on top.
3. Use a toothpick or skewer to swirl the raspberry sauce into the batter.

Step 5: Bake the Cheesecakes

1. Bake for 15-18 minutes until the edges are set but the centers have a slight jiggle.
2. Turn off the oven and let them sit inside for 5 minutes with the door slightly open.

Step 6: Cool and Chill

1. Let the cheesecakes cool to room temperature.
2. Refrigerate for at least 4 hours (or overnight).

Step 7: Add the Finishing Touches

1. Top with whipped cream, fresh raspberries, and a sprinkle of lemon zest.
2. Enjoy your Lemon Raspberry Swirl Cheesecake Cups!