I got this recipe from the Forks and Knives website, and adapted it as follows:
Italian White Bean, Spinach and Potato Stew
1 tablespoon olive oil
1 cup diced red onion
3 cloves garlic or 1.5 teaspoons of diced garlic
Two 28 ounce cans diced tomatoes (salt free if you prefer)
1/2 teaspoon red pepper flakes
5 cups red-skinned potatoes cut into one inch squares
1.5 tablespoons dried oregano
1.5 tablespoons dried parsley
Half a bag of frozen spinach
One 15 ounce can Great Northern beans, (liquid and all)
salt and pepper according to taste
Place a large soup/stock pot over a medium high and pour some of the liquid from one of the cans of the diced tomatoes into the pot to cover the base of the pot and the olive oil. When the tomato liquid starts to bubble, add the onion and stir. Lower heat a little. Press garlic into the pot. Add red pepper flakes (to taste). Continue to cook and stir, lowering heat as the time passes, for a total of about 10 minutes or until onions are soft.
Add the rest of the first can of diced tomatoes and the entire second can into the pot. Bring heat up to medium-high again so that tomatoes begin to simmer. Place diced potatoes, oregano and parsley into the pot and stir. Cover pot, lower heat to low and simmer for 20 minutes. Place all of the spinach into the pot and cover the pot again. Let the spinach thaw. Add Cannellini beans and stir. Taste and season with salt (or not). If potatoes are not as soft as you desire, continue to let simmer. If your potatoes soak up too much liquid (I don’t like my stew too thick) then add a bit of water until you reach your desired consistency.