Turning an existing recipe into a soup starter

How to adapt a soup recipe for the freezer.

I found this recipe for “upvote soup” on Serious Eats a while back and added it to the file of recipes I wanted to try someday (most things in this file have yet to be attempted, as I have saved folders all over the internet of things I’ve never cooked).

But when I was developing my adaptation of Lasagna Soup into a freezer soup starter cube recipe, I was reminded of this recipe, and I thought I’d give it a try. If you'd like to learn more about the idea behind soup starter cubes or find the lasagna soup recipe, you can check out those posts here:

Demystifying the Chicken Noodle Soup Cubes

Lasagna Soup Starter Cubes

What I love most about soup starter cubes is that I can take the time to chop all the veggies, brown all the meat, and build the base flavor of the soup, but then enjoy it multiple times, often weeks apart, and have a fresh pot of soup each time. What I didn’t know yet about this particular recipe is how versatile this base would be.

Sausage and Kale Soup Starter Base

This will make 8 cups of condensed soup base, or four 2-cup soup starter cubes

• 1 tablespoon extra-virgin olive oil

• 1 1/2 pounds mild or spicy Italian sausage, removed from casing

• 1 medium onion, finely chopped

• 3 medium cloves of garlic, finely chopped

• 3 medium celery ribs with leaves, finely chopped

• 1 large carrot, finely chopped

• 1 medium fennel bulb, finely chopped

• 1 1/2 teaspoons fennel seeds

• 1/4 teaspoon crushed red pepper flakes (optional)

• 1/4 cup tomato paste

• 1/4 cup all-purpose flour

• 4 cups homemade chicken or vegetable stock or store-bought low-sodium broth

• 2 cups lacinato or curly kale or other hardy greens, such as collards or Swiss chard, chopped.

Start by chopping all your vegetables. I used my food processor to make this process a bit easier, as I wanted everything except the kale to melt into the soup base. You can leave the veggies larger if you prefer. For the kale, remove the ribs and chop into 1-2 inch pieces.

In a large pot or dutch oven, heat the olive oil over medium heat and cook the sausage, breaking it apart with a wooden spoon, until the fat has rendered and has some crispy edges. Then remove the sausage from the pot with a slotted spoon and add the onions, celery, carrots, garlic, fennel, fennel seeds, and crushed red pepper flakes (if using) to cook in the rendered fat and soften. Scrape up any browned bits from the bottom of the pan while the veggies are cooking.

Next, add the tomato paste to the pot, stirring until it coats the vegetables and the color of the tomato paste deepens. Then add in the flour and stir for an additional 1-2 mintues. Then add in the broth and stir to scrape up anything that has stuck to the bottom of the pan.

Next add in the kale or other hardy greens to wilt, and return the cooked sausage to the pot. Once the kale is wilted, turn off the heat and allow it to cool before transferring the soup base to a freezer-safe container.

I froze this in two 2-cup Souper Cubes molds.

When you are ready to finish the soup, you have some flexibility. For each 2 cups of soup starter base, add 2 cups of broth.

The original recipe calls for adding tortellini, heavy cream, grated parmesan, and pesto.

Once the frozen cube was broken up and the soup was boiling, I added my tortellini directly to the pot and allowed the pasta to cook. Then I added 1/4 cup of heavy cream and ladled the soup into two bowls. Each bowl was topped with a teaspoon of basil pesto. (I forgot the parm this time)

Yesterday I went to make the soup again, but this time I wanted to add potatoes instead of tortellini. I chopped up two Yukon Gold potatoes and added those right to the pot with 2 cups of bone broth.

The potatoes cooked as the soup heated up. This took about 30 minutes on the stovetop, but would have been faster had I diced the potatoes a bit smaller.

Once the potatoes were cooked, I added the 1/4 cup heavy cream, grated Parmesan, and cracked black pepper. Both variations are delicious, and I’m sure you could adapt this recipe to use gnocchi or other starches.