We start by peeling, and then chopping, our onion to yield 1 cup. Half of our yellow pepper we chop, yielding about a third of a cup, to be cooked with the onions. The rest we slice and roast in the oven at 450 degrees until tender (tonight we roast it with the chicken).
In our dutch oven, we add the oil and heat over medium heat. We add the onions and begin softening them, lowering the heat to medium-low. While the onions are cooking, we rinse our cauliflower and chop the florets. We have 2¼ cups of coarsely chopped florets and ¾ cup of smaller pieces of florets that we reserve for the garnish.
Now that the onions have cooked for 10 minutes, we add the chopped yellow pepper to the onions and stir. We continue to cook for five minutes. Then, we add salt and pepper and the coarsely chopped cauliflower, cooking for a few more minutes while we prep the rest of the ingredients.
We peel and mince the garlic with some salt and split the serrano carefully trying not to touch too much of it. We add the garlic, cumin, and serrano to the pot and stir in. We lower the heat to low.
We rinse and then peel the potatoes with our paring knife and coarsely chop, yielding about ½ cup. We strain some of our simmering chicken stock into a 2-cup measuring cup and remove the fat that settles to the top with a spoon. We continue to cook the rest of the cooking stock on the stove. We add the potatoes to the dutch oven, and 2 cups of the hot, strained stock to cover the vegetables. We simmer for another 25 minutes, partly covered, until all the vegetables are very tender.
We remove the serrano and save for garnish. We blend the stock in our blender, in batches, so the hot soup does not “explode”. We add the blended soup back to the dutch oven and add another cup of strained stock to make it the consistency we want.
We microwave the reserved florets for 2 minutes and chop the roasted pepper strips for the garnish for the soup. We add a squeeze of lemon, salt and pepper to the soup, and serve with the florets, roasted pepper, serrano and cilantro.