In a mixing bowl, combine flour and salt. Cut in cold butter until mixture resembles coarse crumbs. Stir in herbs.

Add ice water, one tablespoon at a time, mixing until dough forms. Shape into a disk, wrap in plastic, and refrigerate for at least 30 minutes.

In a skillet, heat olive oil over medium heat. Add sliced onions and cook until caramelized, about 20 minutes.

In a bowl, mix gruyere and cream cheese. Stir in caramelized onions and black pepper.

Preheat oven to 400°F (200°C). Roll out the chilled dough on a floured surface to a 12-inch circle.

Transfer dough to a baking sheet. Spread filling in the center, leaving a 2-inch border. Fold edges over filling.

Bake for 25-30 minutes or until crust is golden brown. Let cool slightly before serving.