Prep your ingredients first. Cut the cauliflower into small, bite-sized florets, slice the onion, and halve or quarter the mushrooms depending on their size. I always mince my garlic fresh and chop the parsley right before using for the best flavor.

Heat a large skillet over medium-high heat. Add the butter and olive oil, swirling to combine as the butter melts. The mixture should sizzle gently but not smoke.

Add the sliced onion to the hot skillet. Cook for 2-3 minutes, stirring occasionally, until the onion starts to soften and become translucent around the edges.

Toss in the cauliflower florets. Spread them in a single layer as much as possible and let them cook undisturbed for 3-4 minutes to get some nice golden browning on one side.

Add the mushrooms to the skillet. I like to nestle them between the cauliflower pieces and spread them out for even browning. Stir gently to combine all the vegetables.

Season with Italian seasoning, salt, and pepper. Sprinkle evenly over the vegetables and toss to coat everything with the herbs and seasonings.

Pour in the vegetable broth and cover the skillet. Reduce heat to medium and let it steam for 5-6 minutes until the cauliflower is fork-tender but still has a slight bite.

Remove the lid and add minced garlic and red pepper flakes. Stir everything together and cook for another 1-2 minutes until the garlic becomes fragrant and the liquid mostly evaporates.

Remove from heat and sprinkle with fresh parsley. Turn off the heat first to prevent wilting the herbs, then give it one final gentle stir and taste for seasoning, adding more salt and pepper if needed before serving hot.