Smoky roasted red peppers and creamy saffron custard are layered over a basic pate brisee crust.
To roast bell peppers, place them directly on a gas burner over high heat. Roast until charred, turning as each side blackens. (Alternatively, roast peppers on a baking sheet under the broiler, turning as each side chars.)
Transfer peppers to a large bowl, and cover with plastic wrap. Let stand until cool enough to handle, about 15 minutes. Using paper towels, peel off blackened skins. Lay peppers flat on a clean work surface. Using a sharp paring knife, remove stems, seeds, and ribs. Finely chop peppers, and set aside.
Preheat oven to 375 degrees. On a lightly floured work surface, roll out pate brisee to a 1/8-inch-thick round about 12 inches in diameter. Brush off excess flour, and wrap dough around rolling pin. Lift it over a 9-inch round fluted tart pan, and place dough in pan. Gently press into sides and bottom. Trim dough flush with edge. Using a fork, lightly prick all over bottom of dough. Freeze 20 minutes.
Remove tart shell from freezer. Line with parchment paper, and fill with pie weights or dried beans. Bake until edge begins to brown, about 20 minutes. Remove parchment and weights, and continue baking until bottom of crust is golden, about 7 minutes more. Transfer to a wire rack, and let cool completely.
Reduce oven temperature to 350 degrees. In a small saucepan, heat the cream over medium-low heat until just warm, and remove from heat. Add the saffron, and let steep, covered, 15 minutes.
In a medium skillet over medium heat, melt the butter. Add shallot, and cook, stirring, until fragrant and soft, 1 to 2 minutes. Stir in the vinegar and reserved peppers. Season with salt and pepper, and set aside.
In a small bowl, whisk together the saffron cream, egg, and egg yolks, and season with salt.
To assemble tart, spread red-pepper mixture evenly over bottom of tart shell. Carefully pour cream mixture over red-pepper mixture. Bake until custard is set, 20 to 25 minutes. Transfer tart to a wire rack; let cool slightly before serving.