Cook the penne pasta in salted water until al dente. Reserve 3 cups of pasta water before draining.
Cook the bacon in a large skillet until crispy. Remove and set aside, but leave the bacon fat in the pan.
Sear the chicken in the same skillet with a splash of olive oil. Season with salt and pepper and cook until golden and cooked through.
Add garlic and red pepper flakes cook for 1 minute. Turn off the heat.
Whisk together eggs, egg yolks, parmesan, sharp cheddar, seasonings and fresh parsley in a bowl. This is your silky, rich carbonara base—don’t worry, you're not eating raw eggs. The heat from the pasta and skillet will gently cook the mixture into a luscious sauce.
Combine it all: Add cooked penne to the skillet, then pour the egg mixture over the top. Toss everything together quickly (off the heat!) until the sauce becomes glossy and coats the pasta. Add splashes of reserved pasta water until you reach the sauce consistency that suits you best.
Toss in the peas, stir it all together, garnish with parsley and more parmesan cheese, and serve hot!