In a large bowl, using electric mixer, beat 2 eggs on high speed for 1-2 minutes. Add flour and continue beating for about 30 seconds to combine. To the same bowl, add spaghetti squash, quinoa, Parmesan cheese, finely chopped spinach,and ¼ teaspoon of salt. Mix very well until all the mixture has uniform consistency. Add chopped bacon and mix. Taste and adjust seasoning, if necessary.
Heat a large skillet on high-medium heat until VERY hot. Only then add oil. It should sizzle and smoke right away.
Using a tablespoon, spoon the tablespoon-ful of the batter for each fritter and drop on the skillet. Using a spatula, correct the shape of each fritter, making it flatter and rounder. Cook until the bottom side of each fritter is golden brown, about 1-2 minutes. Reduce heat to medium.
Using spatula, flip fritters to the opposite side, and cook 1-2 more minutes. When flipping the fritters, you can use a spoon on the opposite side of spatula to help push each fritter onto the spatula and then flipping.
Turn off the heat and let the fritters sit in the skillet (uncovered) for 2-3 more minutes (check the bottom to make sure it's not burned - if it is too dark, remove fritters from the skillet immediately). Do 4 fritters at a time.
Serve as is, or top with the dollop of sour cream or Greek yogurt and chopped green onions (delicious if served this way!).