Important: Set the cream cheese and sour cream out at room temperature for 1 hour before preparing the recipe. Starting with these ingredients at room temperature is the key to a smooth (not lumpy) cheesecake.
To prepare the slow cooker, place a loaf pan inside the center of the slow cooker and pour water around the pan until it comes up to about 2 inches from the top of the pan. Leave the water in the slow cooker while you prepare the cheesecake.
Line the loaf pan with parchment paper (this will make it easy to lift the cheesecake out when it’s done cooking).
Spray the inside of the loaf pan with nonstick cooking spray, making sure to get the ends that are not lined with parchment.
Break graham crackers into large pieces and place them in the bowl of a food processor. Pulse a few times to break down. Add melted butter and 2 tsp sugar and continue to blend / pulse until the mixture resembles wet sand, scraping down the sides if needed.
Press the crust mixture into the loaf pan to form the crust.
Wipe out the bowl of the food processor and return it to the base.
Combine cream cheese, sour cream, 1/2 cup sugar, and vanilla in the food processor.
Blend until everything is evenly combined.
Scrape down the sides and add eggs. (Do not overmix the eggs; this is another key to a smooth cheesecake.)
Blend just until the eggs are fully incorporated.
Pour cheesecake filling over crust.
Transfer cake to slow cooker.
Place 2 layers of paper towels over the top of the slow cooker and then place the lid snuggly on top of the paper towels. (Note: The paper towels will absorb moisture and prevent condensation from dripping down onto the top of the cake.)
Cook on low for 3 hours (or high for 2 hours), until the sides of the cheesecake are light golden brown and the center still looks a tiny bit wobbly.
Use oven mitts to remove the cheesecake from the slow cooker. Let it cool on a wire rack for 1 hour.
Once it has cooled, gently lift the cheesecake out of the loaf pan (using the parchment) and transfer it to the refrigerator.
Refrigerate for at least 4 hours and up to 2 days. Top with preferred toppings. Slice and serve.