Cranberry Orange Shortbread Bars

Wash your hands and clean the work surface. Heat the oven to 350°F (175°C), with a rack in the middle. Line the baking pan with parchment, leaving an overhang on two opposite sides. Rinse the cranberries and orange under running water, scrub the orange rind with a clean produce brush, and dry. Discard damaged cranberries. Finely grate 2 teaspoons orange zest, then squeeze and measure 1/2 cup juice.

In the mixing bowl, beat the softened butter and 1/4 cup sugar with the wooden spoon until smooth and creamy, about 1 minute. Stir in the flour and 1/8 teaspoon salt until a crumbly dough forms and holds together when squeezed.

Press the dough firmly and evenly into the prepared pan, taking care not to make the edges thicker than the center. Prick the surface lightly with a fork. Bake for 28–35 minutes, until the surface is lightly golden and the edges are a deeper golden brown. The base should look dry and baked through, not pale and doughy.

During the final 15 minutes of baking, combine the cranberries, orange zest, orange juice, remaining 3/4 cup sugar, and remaining 1/8 teaspoon salt in the saucepan. Bring to a simmer over medium heat, stirring frequently. Reduce the heat to medium-low and cook for 8–10 minutes, until the cranberries have burst and softened completely.

Set the sieve over the heatproof bowl. Carefully press the hot cranberry mixture through it with the spatula, scraping the underside to collect the smooth pulp. Discard the skins left in the sieve. Return the strained filling to the saucepan.

Whisk the cornstarch with the cold water until completely smooth. Stir the slurry into the warm cranberry filling. Bring to a gentle boil over medium heat, stirring continuously and scraping the bottom and corners. Once bubbles break across the surface, cook for 1 minute, stirring, until thick and glossy. Remove from the heat; avoid prolonged boiling.

Place the baked shortbread, still in its pan, on the cooling rack. Pour the hot filling over the warm base and spread it into an even, smooth layer that reaches the edges. Do not add a topping.

Cool uncovered in the pan for 1 hour, then refrigerate for at least 2 hours, until the filling is completely cold and firm enough to slice. Cover once cold.

Lift the chilled slab out using the parchment overhang and place it on the cutting board. Cut into 16 equal squares with a sharp knife, wiping the blade clean between cuts. Serve chilled, or let the cut bars stand for 10–15 minutes for a softer bite.