Cut the bacon in 1/2 and lay on the rack in the high position. AC on 360° F for about 14 minutes (less if your pot is preheated). Flip at 7 minutes. Adjust the time if needed for the bacon to be crispy and have a lot of the fat rendered out. Remove and drain on paper towels. Reserve the fat that is in the inner pot.
Cut the onion in 1/4" size dice. Cut the chicken into 1 -1 1/2 inch cubes.
Turn on the Sear/Saute on high and allow the bacon grease to heat up. Add diced onions and cubed chicken and the salt. Saute for 2-3 minutes.
Add 2 cups of chicken stock and 2 bulbs of roasted garlic. Add spaghetti noodles either by breaking them in half and alternating layers or by using a canning rack and leaving them whole. See post for details!
Put the pressure lid on and turn the valve to seal, Set the Ninja Foodi to high pressure for 6 minutes. Adjust time up for softer pasta. Allow to natural release for 3 minutes and then release the remaining pressure.
Scrape the noodles out of the rack if using and into the inner pot and stir so the noodles are submerged in the liquid. This will finish cooking and absorb the liquid. Turn the Ninja Foodi off.
Add 2 cups of freshly grated Parmesan cheese and stir to combine. Close lid and wait about 5 minutes to allow the cheese to melt. If you think there is too much liquid, it does thicken as it cools, but you can also sear/saute to reduce some liquid if you want. You can also add in the extra 1/2 cup of grated Parmesan cheese. Make sure to let the pot cool down a little before adding in the eggs.
Whisk together 3 eggs until well combined and you have a consistent yellow color. You don't want to see streaks of egg whites. Slowly add in the three eggs and stir. Please see post for troubleshooting tips. Add crumbled bacon and stir.
Top with additional grated Parmesan Cheese and freshly cracked black pepper. Serve and Enjoy.