Set cooker (8 qt) to saute-high. Note: If you have a 6 qt IP, cut the recipe in half.
Place the ground beef and Italian sausage in the cooker. Mix and crumble the meat; cook for 4 minutes or until no longer pink. Optional: transfer the meat to a strainer and drain the grease.
Add onion, garlic and cook for 1 minutes or until the onion becomes translucent.
Add salt, pepper, sugar, red flakes, Italian seasoning and tomato paste; mix.
Pour in the beef broth, add chopped/diced tomatoes and stir.
Add broken lasagna noodles (about 2"). Make sure to submerge the noodles under the broth. Press cancel button.
Pressure cook on high for 4 minutes, then natural release for 5 minutes (it will take about 15-18 minutes to come to atmosheric pressure). Follow the manufacture instructions when preparing to removing the lid (as you release the pressure using the vent).
Add half (or all if you prefer) the ricotta mixture to cooker and mix well. Cover with the lid for 5-6 minutes before serving (this will thicken the soup).