Season both sides of lamb with salt & pepper.
Set Instant Pot to Sauté mode. Add 1 T of avocado oil. Then add lamb, sear both sides for 3-4 minutes until browned. Remove lamb from instant pot and set aside.
Add 1 T of avocado oil and onion. Sauté 3 -4 minutes. Then add garlic, sauce for 30 seconds and stir. Add in red pepper. Sauté for 2 minutes.
Now pour in crushed tomatoes, tomato paste, herbs, and red pepper flakes. Stir and let simmer for 2-3 minutes
Add lamb back to the IP along with beef bone broth and bay leaf. Secure the lid. Set Instant Pot to Meat or Pressure Cook mode on HIGH for 40 minutes. Do a natural release for 10 minutes. Remove shank from IP and shred the meat. Add lamb meat back to the IP with the sauce.
Bring a pot of water to a boil. Season with salt. Add in pappardelle pasta, cook until al dente.
Toss lamb ragu with pasta. Top with pieces of burrata and dollops of basil pesto. Devour!