In a skillet, lightly sauté to remove any liquid from the ham. Remove from heat and cool.
Preheat waffle maker.
In a mixing bowl or large measuring cup, combine the eggs and heavy cream, and mix well using a fork or whisk. Add the sea salt, black pepper, cooled ham, cheese, and chopped spinach to the bowl. Stir well to combine.
When the waffle maker is hot, lightly spray the top and bottom waffle plates with the avocado oil cooking spray. Using a large spoon, ladle the egg mixture into each section of the waffle maker and spread it out. The grids should be covered, but not overflowing.
Close the waffle maker and hold the handles together for 10 seconds, stream will release from the sides. Release the hold on the handles and let the waffle omelet cook for 1-2 minutes or until the egg has cooked through. Use a fork to remove the cooked waffle omelet, plate, and cover. Repeat until all your batter is used.
Top with sliced green onions and salsa on the side. Serve immediately.