Cook pasta according to the directions on the package.
Place drained piquillo peppers in a blender and set aside.
Heat 2 tablespoons extra virgin olive oil in a nonstick skillet.
Add sliced onions, garlic, thyme, salt and ground pepper; cook for 4 minutes, stirring frequently, until tender.
Remove from heat and transfer the onion mixture to the blender.
Add water and blend until completely smooth.
If too thick, add a tablespoon or two of extra virgin olive oil or water and continue to blend until desired consistency is reached.
Taste for seasonings and adjust accordingly.
Heat remaining extra virgin olive oil in a skillet.
Add spinach and cook for 2 minutes, or until wilted.
Drain pasta and add to skillet with spinach; stir in feta cheese and add as much pepper sauce as you prefer and toss around to combine.
Remove from heat and serve.