• Position a rack in the center position of the oven. Preheat the oven to 350ºF (177ºC).
• Line an 8″ x 8″ (or 9" x 9") baking pan with foil. Leave an overhang on the sides. Set aside.

SHORTBREAD CRUST

• Stir the melted butter, granulated sugar, vanilla extract, salt, and the lemon zest together in a medium bowl. Add the flour and stir until combined.
  1 cup (227g) unsalted butter, ½ cup (100g) granulated sugar, 2 teaspoons vanilla extract, ½ teaspoon salt, 2 cups (240g) all-purpose flour
• Reserve ¾ cup³ of the shortbread crust and place in the refrigerator or freezer until needed.
• Press remaining crust evenly into the prepared pan. Bake for 18 minutes while you prepare the filling.

RASPBERRY SWIRL

• In a small saucepan over medium heat, combine the raspberries, cornstarch, lemon juice, and sugar.
  1 cup fresh raspberries¹, 1 teaspoon cornstarch, 1 Tablespoon (15mL) fresh lemon juice, 1 Tablespoon (8g) granulated sugar
• Cook the mixture while stirring frequently and mashing the raspberries as you stir. Continue cooking until the mixture is starts to thicken and is no longer slightly cloudy (about 10 minutes).
• Remove the raspberry mixture from the heat and let it cool while you make the filling.

FILLING

• In the bowl of a stand mixer fitted with the paddle attachment, or in a medium sized bowl with a hand mixer, beat cream cheese on high until smooth. Add the sugar and beat until smooth.
  8 ounces (225g) cream cheese, 1 cup (200g) granulated sugar
• Add the eggs, and continue beating until completely incorporated. Add the yogurt, lemon juice, and salt and beat again. Finally, add the flour and beat one more time until just combined. Scrape down the sides as necessary before adding the raspberries, then gently fold in them in with a large spatula.
  2 large eggs, 5 ounces (150g) yogurt or sour cream², 2 teaspoons fresh lemon juice, ¼ teaspoon salt, ½ cup (60g) all-purpose flour, 1 and ½ cups (150g) raspberries
• Pour the filling into the prepared crust, the dollop the raspberry swirl evenly over the filling. Use a butter knife to gently swirl the raspberry mixture into the filling, then scatter the fresh raspberries around the top of the filling/raspberry swirl.
• Remove reserved crust from refrigerator and crumble over top of the filling (you may need to separate into crumbs with a knife or fork). Sprinkle with additional sugar or course sugar, if desired. 
• Bake the bars for 55-60 minutes minutes, or until a toothpick inserted in center comes out clean. Allow bars to cool at room temperature on a wire rack. When completely cool, chill in the refrigerator for 1 hour.
• When bars are completely chilled, lift out of the pan using foil overhang and cut into squares. Bars can be stored covered in the refrigerator up to 5 days. Bars freeze well, up to 3 months. Thaw in the refrigerator overnight.