• Line the bottom of an 8-inch springform pan with parchment paper.

Make the Crust

• Preheat oven to 350°F.
• Place all the graham crackers in a food processor and pulse until they are completely broken up. Add the sugar and pulse to combine.
• Add the butter and pulse until it is uniformly mixed in. Press the mixture into the prepared pan, pushing the crumbs up the side of the pan. Bake until toasty and lightly browned, about 15 minutes. Allow to cool.
• Turn the oven down to 300℉.

Mix Cheesecake

• In a stand mixer fitted with a paddle attachment on low speed mix the cream cheese, until smooth. Scrape the bottom and sides of the bowl with a rubber spatula. Add the yogurt, sugar and zest, continue mixing until smooth. Scrape the bowl again. Add the eggs, one at a time, scraping the bowl after each addition. Add vanilla and mix until combined.
• Bake at 300°F for about 1 to 1 1/2 hours (check at 1 hour to see if it is setting up. The time is such a wide range because the temperature of the ingredients will play a big part in baking times.)
• The cheesecake is done when the center moves like set jello when you gently shimmy the pan. If it is still liquid, continue baking until it is set properly.

Adding Topping (optional)

• While the cheesecake is baking make the topping: In a medium sized bowl, stir together the yogurt, sugar and vanilla. Set aside at room temperature until cheesecake is baked.
• Once the cheesecake is baked, remove it from the oven. Gently spoon the topping over the still hot cheesecake in several additions. The cheesecake will still be fragile while it is hot, so you want to work gently as to not break through the top. Using an offset spatula, spread the topping over the cheesecake.
• Bake for 8 more minutes, no longer.
• Remove from oven, immediately run a knife, dipped in hot water, around the edge of the pan, just about 1/2-inch-deep. This will help to prevent the cake from cracking and will make removing it easier once it is fully cooled.

  Cool to room temperature, then refrigerate in the pan for several hours or overnight.
• Once the cake is thoroughly chilled. Run a knife, dipped in hot water, around the cake again, this time going a bit deeper into the pan, about 2-inches. Release the springform pan and move the cake to a serving platter.
• Add fresh berries to the top and serve. The cake can be made a day or two ahead.