Cook bacon in large skillet over medium heat. When crispy, remove from pan and place on paper towels. Cool, then crumble into pieces. Drain off all but 1 tablespoon of the bacon fat from the skillet.
Add butter to the skillet and saute the red onion for a minute or two over medium heat. Then add the corn, red bell pepper, jalapeno, and red pepper flakes. Season with garlic salt and black pepper while cooking.
Cook, stirring often, until corn is tender, about 7-10 minutes. Add a splash of chicken broth (or water) if you see the corn mixture getting too dry or sticking to the pan while cooking.
Stir in the spinach and all but one handful of the green onions. Stir for a minute or so, until the spinach leaves wilt down a bit.
Top the corn mixture with the crumbled bacon, the parmesan cheese, and the rest of the green onions. Serve with your favorite hot sauce, if desired. Enjoy!