Preheat oven to 350°F
Wash, peel and chop the beets
Chop 1 onion
Coat the beets and onions with olive oil, add pinch of salt and pepper and bake for 30 minutes (cover with foil to prevent over-browning)
Add the feta into the tray and pop the foil back on top. Cook for a further 10 - 15 minutes.
Put the beets, feta and onions in a blender with 1 cup of chicken broth and blend
Chop 1 onion and peel the garlic and slice or use a garlic press
Add butter and onions to a pot and sauce for 5 minutes
Add garlic and cook for an additional minute
Add thyme and cook
Add beet, feta and onion mixture with 2 cups of chicken broth, oregano, basil and bayleaf to the pot; stir and cook for 20 minutes
Remove from heat and add fresh lemon juice
Cook the rigatoni for the packet time
Reserve some pasta
Combine rigatoni and beet sauce
Use a ladle to scoop the pasta into a bowl
Sprinkle feta, chili flakes and chopped parsley to each bowl