Preheat your oven to 325°F (160°C) and line a mini muffin tin with paper liners.

In a mixing bowl, combine the graham cracker crumbs, melted butter, and sugar until the texture resembles wet sand.

Press about 1 firmly packed tablespoon of the mixture into each liner, ensuring an even crust.

Bake the crust in the oven for 5 minutes, then remove and set aside to cool.

In a separate mixing bowl, beat the softened cream cheese and ⅓ cup sugar with an electric mixer on medium speed for 1-2 minutes until smooth.

Add the egg and vanilla extract to the cream cheese mixture and mix on low speed until just combined.

Stir in the sour cream or Greek yogurt until the batter is creamy and well combined.

Either spoon or pipe the cheesecake filling into each muffin cup, filling almost to the top.

In a small bowl, mash the raspberries, 1 tsp of sugar, and lemon juice together. Strain if a seedless puree is desired.

Place a small dot of raspberry puree in the center of each unbaked cheesecake and use a toothpick to drag it into a heart shape.

Bake the cheesecakes in the preheated oven for 15-18 minutes. Edges should be set while the centers jiggle slightly.

Let them cool completely in the pan before chilling in the refrigerator for at least 2 hours, or overnight for best results.