2 tablespoons chopped almonds or walnuts, optional
In a large skillet, saute the leeks, red pepper and garlic in oil until tender. Remove from the heat; cool for 5 minutes. Stir in the cheese, mustard and herbs; set aside.
On a lightly floured surface, roll each sheet of crust into a 12-in. circle. Transfer to parchment-lined baking sheets. Spoon leek mixture over crusts to within 2 in. of edges. Fold edges of crust over filling, leaving center uncovered. Brush folded crust with milk; sprinkle with nuts if desired.
Bake at 375° for 20-25 minutes or until crust is golden and filling is bubbly. Using parchment, slide tarts onto wire racks. Cool for 10 minutes before cutting. Serve warm. Refrigerate leftovers.