Add chicken broth, Dijon mustard, and paprika to pot and give a good mix. Then add butter, pasta, and finally salt. Lock lid and cook for 3 minutes at high pressure.
Once cook time is complete, quick-release pressure. Remove lid then switch to sauté setting.
Add truffle oil and evaporated milk - gently mix well.
Once it comes back up to a boil, switch to keep warm setting.
Add both cheeses ½ cup at a time, mixing well until all shreds have melted.
Gently give a good mix. Serve as soon as possible for creamiest consistency.
If you choose to use elbow pasta, increase cook time to 4 minutes.If starchy bubbles try to escape the vent when releasing pressure, simply close the vent and try again in 30 seconds - releasing a little bit at a time.