Make the crust:

1. In a food processor or bowl, mix flour and salt. Add butter and pulse (or cut in with a fork) until the mixture resembles coarse crumbs.
2. Gradually add ice water, 1 tablespoon at a time, until the dough just comes together.
3. Shape into a disc, wrap in plastic, and refrigerate for 30 minutes.
4. Roll out on a lightly floured surface to fit a 9-inch tart pan or pie dish. Press into the pan, trim excess, and prick the bottom with a fork.
5. Chill for 10 minutes while preheating the oven to 375°F (190°C).
6. Line the crust with parchment paper and pie weights or dried beans, then bake for 15 minutes. Remove weights and bake another 5 minutes until lightly golden. Set aside.

Prepare the filling:

1. In a skillet over medium heat, heat olive oil. Add shallots and sauté until soft (about 2 minutes).
2. Stir in garlic and greens, cooking until wilted (about 2-3 minutes). Season with salt and pepper. Remove from heat.

Assemble and bake:

1. In a bowl, whisk eggs and cream until smooth. Stir in grated cheese and crumbled bacon.
2. Spread the cooked greens mixture over the pre-baked crust. Pour the egg mixture on top. Sprinkle with crumbled feta or goat cheese.
3. Bake at 350°F (175°C) for 35-40 minutes or until the center is just set.
4. Let cool slightly before slicing.

Serve warm or at room temperature. Pairs well with a simple side salad.