1. Preheat your oven to 375°F.

2. Fill a small saucepan with water and bring to a boil. Fill a medium-sized bowl with iced water and set aside. Cook spinach in boiling water for 2 minutes, remove from the saucepan, and put into the ice water until cool. Drain the water from the spinach and use a paper towel to soak up any excess water.

3. Chop drained spinach and add to a medium-sized bowl. To the same bowl, add ricotta and diced onion. Season with salt, pepper, and garlic powder.

4. Using a large biscuit cutter, cut circles out of the pie crusts and place on a parchment-lined baking sheet. Onto each pie crust, add a layer of the ricotta filling, making sure to leave at least a half an inch border of crust. Add a tomato slice and a handful of sausage slices to each galette.

5. Fold the border of the crust on each galette over, pinching the crust together when needed to keep the shape. Using a pastry brush, brush the whisked egg over the folded pie crust and sprinkle with everything bagel seasoning.

6. Bake the galettes for 20 minutes, or until the dough is golden.

7. Garnish galettes with a sprig of thyme.