The end of growing season calls for this easy and delicious Green Tomato Soup! We treat the tomatoes to a nice sauté with the onions to help reduce their tartness, while developing a deep caramelized flavor that pairs well with the roasted garlic.
Remove outer paper of the heads of garlic, allowing them to still stay together. Cut the tops off the heads, exposing the cloves.
Place each head on a small square of foil, and drizzle with ½ tablespoon of oil each.
Wrap the heads in the foil, and place in the oven for about 30 minutes, until all the cloves are very soft (like butter).
If you are making the croutons, make them now, while the garlic roasts!
Remove garlic from the oven, and unwrap the heads to allow them to cool.
Make the Soup
Heat 1 tablespoon oil in a large skillet, and sauté the onions, salt and pepper, until browned and very soft, about 15-20 minutes.
In the last 5 minutes of sauteing, add the chopped green tomatoes, and continue cooking.
Pour the vegetable stock into the pot, along with the thyme, and bring to a boil. Reduce heat to medium-low, and simmer until the tomatoes are soft, about 5-10 minutes.
To the blender, add the spinach and roasted garlic.
Pour the tomato mixture over the spinach in the blender.
Puree on high until the soup is very smooth, about 2-3 minutes.
Return the soup to the pot (off the heat), and stir in the baking soda.
The soup will start to bubble as the baking soda neutralizes some of the acid. Continue stirring until the bubbling stops, and all the bubbles dissipate.
Pour into bowls, and garnish with croutons, fresh thyme, and a sprinkle of nutmeg, as desired.