Preheat your oven to 325°F (160°C). In a bowl, mix crumbled Oreos and melted butter until well combined. Press this mixture firmly into the bottom of a parchment-lined 9x9-inch baking pan. Bake for about 10 minutes, then let it cool.

In a large mixing bowl, beat softened cream cheese with sugar until smooth. Add in the eggs, one at a time, and mix until fully incorporated. Stir in the vanilla and the strawberry puree until mixed thoroughly.

Pour the cheesecake mixture over the cooled Oreo crust, smoothing it out evenly. If you're using sour cream, gently fold it in for extra creaminess at this stage.

Bake at 325°F (160°C) for 30-35 minutes, or until the edges are set but the center still has a slight jiggle. Allow it to cool completely before refrigerating for at least 4 hours or overnight.

Once fully chilled, lift your bars out of the pan using the parchment paper. Top with chopped strawberries and a sprinkle of crushed Oreos if desired, then slice into squares.