This keto zucchini recipe is brought to you by Fiesta Brand Seasonings!
If you love cheesy au gratin potatoes, you’re going to fall in love with Keto Zucchini Gratin with Poblano Peppers. This gorgeous, delicious zucchini recipe is spiced up with cumin and poblano for a simple, easy, and drool worthy keto side dish with some Texas flare, that your family and guests will go crazy for!

Lately, Maddie and I have been in a keto side dish rut. I’ve been finding myself skipping the side dishes all together and just topping my protein with a couple slices of avocado or a spoonful of guacamole. Honestly, the lack of a side dish really doesn’t bother us, but I know with the holidays quickly approaching that I need an easy keto side dish we can get excited about and delicious enough to serve to our guests! And this Keto Zucchini Gratin is over the top amazing!
As far as keto side dishes, anything “au gratin” is at the top of my list. Au gratin potatoes were always a favorite as a kid, so I decided to gratin one of our favorite keto veggies…zucchini! That caramelized, crispy brown top is everything!! This keto zucchini recipe is spiced up with cumin and uses poblanos for a little Texas flare, so easy and incredibly delish!

Perfect for entertaining, this one skillet wonder is done in less than 30 minutes!
This Keto Zucchini Gratin is made in a skillet, then put into the oven to finish cooking and to create that tasty brown crust that everyone goes crazy for! A cast iron skillet is great to use here but if you don’t have one, make sure to use an a skillet that’s oven safe up to 400 degrees.

The process for this keto zucchini recipe is so simple, which makes it perfect for the holidays! First, the onion and poblanos get sautéed in some butter until tender. Then the garlic and cumin are added and cooked for another minute. The sliced zucchini then goes into the pan and sautéed with the onion and poblanos until just tender. In goes the cream, cheese and sour cream, and everything gets gently tossed together, topped with cheese and into the oven!

I like to use Monterey Jack cheese, or if you like spice, use Pepper Jack for a little additional heat!
How to Serve This Keto Zucchini Gratin
I like to serve this keto side dish right out of the skillet topped with a little Mexican Crème, chopped parsley, and crumbled Queso Fresco or Cotija cheese for a little extra oomph, but its amazing just as it comes out of the oven!

This Keto Zucchini Gratin is a show stopper and one of the tastiest side dishes we’ve had in quite some time. This dish would be perfect served up for the holidays next you a prime rib or as a quick and easy weeknight keto side dish! Done in under 30 minutes and kid & Cowboy approved!
Looking for other delicious keto sides? Check these out!
- Whole Roasted Cauliflower with Pimento Cheese Butter
- Mexican Street Style Grilled Cauliflower
- Marinated Artichoke Salad
Keto Zucchini Gratin with Poblanos
Ingredients
- 3 Tbsp. butter
- 1 small onion diced
- 2 poblano peppers seeded and diced
- 4 zucchinis cut in half lengthwise and sliced
- 1 clove garlic
- 1 ¼ tsp. cumin
- ½ tsp. garlic powder
- ¾ cup heavy cream
- 1 ½ cup shredded Monterey Jack cheese or Pepper Jack divided
- 2 Tbsp. sour cream
- 1 ¼ tsp. salt divided
Garnish: Mexican Crema, Chopped Parsley, Cotija or Queso Fresco
Instructions
- Preheat oven to 400 degrees.
- In a large oven safe skillet over medium heat, melt the butter, add the onion, poblano, ½ tsp. salt and cook until tender, 5-7 minutes. Add the garlic and cumin and cook for another minute. Add the sliced zucchini, season with ½ tsp. salt and continue to cook 5 more minutes or until zucchini is tender.
- Stir in the cream and cook for another minute. Remove from the heat and stir in 1 cup cheese, sour cream, and remaining ¼ tsp. salt.
- Top with the remaining cheese and bake for 10-12 minutes or until bubbly. Turn the broiler on high and cook for another 2-3 minutes or until top is browned. Remove from oven and let sit 5 minutes before serving.
Notes
Nutrition
Nutrition facts are approximate and will vary depending on the ingredients used. Carbs from sugar alcohols have been excluded since they have shown to have no impact on blood sugar.