Mini Hash Brown Frittatas

1. Preheat oven to 375°F. Coat a 12-cup muffin pan with baking spray. Toss together hash browns and 2 cups of the cheese in a large bowl until combined. Spoon hash brown mixture evenly into prepared pan, filling all cavities (about ½ cup each), pressing up and around sides to form a cup. Bake until edges are golden and crispy, about 30 minutes.

2. Meanwhile, place spinach in a clean kitchen towel; squeeze to remove liquid. Melt butter in a medium skillet over medium-high. Add onion. Cook, stirring occasionally, until translucent and tender, about 5 minutes. Reduce heat to low. Add spinach, and cook, stirring occasionally, just until spinach is warmed and combined with onion, about 1 minute. Remove from heat, and set aside until ready to use.

3. Remove baked hash brown cups from oven, and spoon 1 heaping tablespoon onion-spinach mixture into bottom of each cup. Whisk together eggs, half-and-half, salt, and pepper in a large bowl until eggs are beaten and mixture is well combined. Carefully pour evenly into hash brown cups to cover onion-spinach mixture. Top evenly with tomatoes, and sprinkle with remaining ½ cup cheese.

4. Bake at 375°F until eggs are set and hash browns are crispy and browned, about 30 minutes. Remove from oven; cool on a wire rack 5 minutes. Serve warm.

Chef's Notes

Make Them Ahead: Place cooked, cooled frittatas in a ziplock plastic bag, and press out air before sealing and freezing. To reheat, thaw in the refrigerator; then remove from the bag, and microwave 1 minute or bake at 350°F until heated through, 5 minutes.