Pre-heat oven to 400 degrees.
Place halved tomatoes and garlic in peel on a foil-covered baking sheet lightly brushed with olive oil. Lightly brush a little bit more olive oil over tomatoes and garlic. Roast for about 40 minutes, until the tomatoes are getting wrinkled.
Put onion and habanero in a large stockpot with 1 Tbsp olive oil. Sauté for about 5 minutes, until onion is translucent.
Remove peels from garlic and add garlic and tomatoes to stockpot. Add vegetable stock and sugar to stock pot, as well.
Using an immersion blender, blend until soup is smooth. Alternatively, you can put the soup in a blender and puree until smooth.
Let soup simmer for about 20 minutes, until thickened. Mix in quinoa and feta cheese.
Serve and top with basil and additional feta cheese, if desired.