Jesuitas Recipe

Prepare pastry

Remove puff pastry from the refrigerator and keep it covered while you preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper. On a lightly floured surface, roll each thawed sheet briefly to smooth seams and to roughly 12 x 9 inches.

Make burnt sugar (caramel) glaze

Place a heavy-bottomed medium skillet over medium heat. Add the granulated sugar (6 tbs) in an even layer. Without stirring initially, let the sugar begin to melt at the edges. Once melting starts, swirl the pan gently or stir with a silicone spatula to encourage even caramelization. Continue cooking until the sugar reaches a deep amber color but not bitter (watch closely; this happens quickly). Remove from heat and immediately stir in the cold unsalted butter (2 tbs) in pieces — the mixture will bubble. Work quickly and carefully until the butter is incorporated and you have a glossy caramel. If it thickens too much, add a teaspoon of warm water to loosen. Set aside briefly (1–2 minutes) to cool slightly but remain pourable.

Glaze and par-bake pastry

Working quickly so the caramel stays fluid, brush or pour a thin, even layer of the burnt sugar glaze onto one side of each pastry sheet. Place the glazed side up. Using a knife or pizza cutter, score a 1/2-inch border around the edges of each sheet (do not cut all the way through). Transfer the baking sheet to the oven and bake for 10–12 minutes, until pastry has puffed and the edges are golden brown. Remove from oven and reduce oven temperature to 375°F (190°C).

Once the glazed pastry is hot and glossy, very gently press down the center of each puffed sheet (inside the scored border) to deflate slightly and create a shallow well for the filling. Arrange half of the prosciutto slices (4 slices) over each pastry sheet in an even layer, trimming if necessary to fit inside the border. Top the prosciutto with the sliced Gruyère or fontina (about 1/2 cup per sheet), distributing evenly.

Return the filled pastries to the oven (375°F / 190°C) and bake for an additional 5–7 minutes, until the cheese is melted and slightly bubbling and the edges are deeply golden. Remove from the oven and let cool 2 minutes on the sheet.

If using arugula, toss it lightly with a small pinch of salt and a grind of black pepper. Top each warm tart with the fresh arugula (about 1/2 cup per tart). Finish with a light sprinkle of flaky sea salt (about 1/4 tsp each) and freshly ground black pepper to taste.

Optional: If you prefer a glossy, deeply colored edge before adding prosciutto (instead of glazing before baking), whisk the egg with 1 tsp water to make an egg wash and brush the pastry borders before the first bake. In the method above the caramel acts as the glaze; use egg wash only if you skipped glazing initially.

Serve warm: slice each sheet into two or four portions depending on size and serve immediately so the caramel remains slightly crisp and the cheese is melty. Estimated serving suggestion: two pastries serve 4 people as appetizers or 2 as a light meal.