Step 1
Turn on a multi-functional pressure cooker (such as Instant Pot®) and select Saute function. Add onions butter paprika salt and black pepper. Cook and stir about 4 minutes. Add wine; close and lock the lid. Select manual and high pressure and set timer for 20 minutes. Allow 10 to 15 minutes for pressure to build.
Step 2
Release pressure carefully immediately after timer goes off using the quick-release method according to manufacturer's instructions about 5 minutes. Unlock and remove the lid. Add sherry and select saute mode. Cook for 3 minutes scraping up any browned bits from the bottom of the pot.
Step 3
Add 6 cups broth and bay leaf to the pot. Close and lock the lid; select manual and high pressure and set the timer for 6 minutes. Allow 10 to 15 minutes for pressure to build.
Step 4
Meanwhile mix flour and remaining 1 cup broth together in a bowl.
Step 5
Release pressure carefully immediately after timer goes off using the quick-release method according to manufacturer's instructions about 5 minutes. Unlock and remove the lid.
Step 6
Set pressure cooker to saute and remove and discard bay leaf. Add flour-broth mixture and cook and stir until soup is thickened about 10 minutes. Season with salt and black pepper.
Step 7
Set an oven rack about 6 inches from the heat source and preheat the oven's broiler.
Step 8
Ladle soup into oven-safe serving bowls and top each with slices of baguette and Gruyere cheese. Broil soup bowls until bread is toasted and cheese is melted 1 to 3 minutes.