Preheat your oven to 350°F (175°C) and lightly grease an 8x8 inch baking pan. In a medium bowl, combine graham cracker crumbs and melted butter, mixing until well combined.

Press the mixture evenly into the bottom of the prepared baking pan to form the crust. Bake for 8-10 minutes, then remove from the oven and let it cool slightly while you prepare the filling.

In a large bowl, beat the softened cream cheese and granulated sugar together until smooth and creamy. Add the egg and vanilla extract, continuing to beat until just combined.

Pour the cream cheese mixture over the pre-baked crust in the baking pan, spreading it evenly. Bake for 25-30 minutes, or until the center is just set.

Remove the pan from the oven and let it cool completely on a wire rack at room temperature. Once cooled, refrigerate for at least 2 hours to allow the cheesecake to firm up.

Once the cheesecake is chilled and firm, arrange the sliced fresh strawberries over the top. In a small bowl, warm the strawberry jam slightly to make it easier to spread, then drizzle it over the strawberries.

Cut into bars and serve immediately. Store any leftover cheesecake bars in an airtight container in the refrigerator for up to 3-4 days.