Preheat oven to 425. Spray a 12-cup muffin tin with cooking spray.

Heat 1 tablespoon of avocado oil in a skillet and heat to medium high. Add onion and cook for 8 minutes, stirring occasionally. Reduce heat to medium and add thyme, salt and pepper. Cook for an additional 10 to 15 minutes and add garlic and vinegar. Cook for 30 seconds and remove from heat. Add another teaspoon of the oil to the skillet and cook spinach until wilted. Transfer to a strainer and press out excess moisture.

Roll out dough on parchment paper sprinkled with extra flour into a 9 x 13 inch rectangle. Brush with the remaining 2 teaspoons of oil. Spread the onions and spinach over the dough and then sprinkle the cheese. Carefully roll into a log, starting with the long side. (Lift the parchment paper as needed to help you roll.) Cut into 12 slices and place in prepared tins.

Cook until golden brown, about 20 minutes. Let cool for 5 minutes and serve warm.