Preheat oven to 325F. Prep a 12-cavity cupcake pan by lining it with paper liners. Set aside.
In a medium bowl, stir ¾ cup graham cracker crumbs, 1 ½ tablespoons sugar and 3 ½ tablespoons melted butter until the crumbs are evenly moist.
Scoop about 2 teaspoons of the crumbs into each cupcake cup and press firmly down to the bottom of pan (see note).
Bake for 5 minutes then take out of the oven and set aside to cool (keep the oven on). In the mean time, work on your cheesecake filling.
For the Cheesecake Filling:
Using a handheld electric mixer or a stand mixer fitted with the paddle attachment, beat the cream cheese until smooth.
Add ¾ cup sugar, 1 tablespoon flour and 1 teaspoon lemon zest and beat until well combined.
Add the eggs, one at a time, until each one is incorporated.
Then add 1 teaspoon vanilla and ¼ cup sour cream and stir until just combined. Remember to scrape the bottom and sides of your bowl.
Optional step for the creamiest cheesecake: transfer the mixture into another bowl by straining using a fine mesh sieve.
Scoop the mixture into your prepared baking pan (each cup ⅔ full) and gently drop the pan a few times on the counter to release any air bubbles.
Bake for 20-25 minutes or until the cupcakes are puffy (don't worry, they will deflate as they cool).
Remove from oven and cool completely in the pan before putting them in the fridge to set completely (3-4 hours).
I use a shot glass to press down the crumbs into the cupcake pan - works very well!
Do you want to put swirly jam on top? Before putting the cheesecakes into the oven put 4-6 drops of jam (I warmed mine in the microwave for a few seconds to make them more spreadable) on top and make swirls using a toothpick or small knife.
For other toppings (like salted caramel), you can top the cheesecakes before serving.