This soup has the spirit of a gumbo, but is gluten free as it uses lentils to thicken it instead of the traditional roux. It is also versatile in that you can add, subtract, or swap different vegetables, proteins, or herbs. For example, the original recipe calls for 4oz of smoked ham, and I have made it that way a couple times, but next time I will probably use about 1/2C of small shrimp instead.
The soup freezes well and, in my opinion, tastes just as good served cold on a hot day. When serving, my understanding is that it is traditional to first add a portion of steamed rice to the bowl first. If I were to use rice, I might add about one cup of unwashed, (to maintain the outer starch coating to add more thickening), long-grain rice along with the lentils and cook everything together, but I have not tried that. The biggest thing to keep in mind is that salt can retard the softening of the lentils. Therefore, I only use a little salt when cooking to bring out some of the water from the vegetables, and use salt-free stock. I do add salt at the end and recommend doing so, but that is up to you and your tastes. If using shrimp, I would add it about 5 (fresh) to 10 (frozen) minutes before the end of cooking so they do not get rubbery.
A full written recipe may be found here: https://cook.karylstein.com/g/family/r/green-lentil-gumbo.