Preheat your oven to 350°F (175°C) and line a 9x13-inch baking pan with parchment paper.

In a mixing bowl, combine all-purpose flour, granulated sugar, and salt. Cut in the unsalted butter until the mixture resembles coarse crumbs. Add vanilla extract and press into the bottom of the prepared pan. Bake for 18-20 minutes.

In another bowl, whisk together more granulated sugar, flour, and salt. Incorporate eggs, fresh lemon juice, and zest, mixing until smooth. Fold in melted butter gently.

In a small saucepan, combine cranberries, sugar, and a splash of water. Cook until cranberries soften and mixture thickens, about 10 minutes. Mash some berries and allow to cool.

Pour the lemon filling over the baked crust and dollop the cranberry mixture on the surface. Gently swirl with a knife.

Bake for 30-35 minutes until the edges are set and the center has a slight jiggle.

Let cool completely in the pan, then chill in the refrigerator for 2-3 hours.

Lift out of the pan using parchment overhang, slice into squares and dust with powdered sugar before serving.