Pressure Cooker French Onion Soup

I LOVE French onion soup.  I HATE the way my house smells for days when I make French onion soup.  Looking forward to trying this recipe.

3 tbsp. butter
3lbs. onions, sliced
1/2 tsp. baking soda
3 tbsp. Worcestershire sauce
1 tsp. dried thyme
1qt. beef broth
16 French bread slices (1/2 thick)
3/4 C. finely shredded Parmesan cheese
3 tbsp. apple cider vinegar

Melt butter in pressure cooker, using the sauté setting.  Add onions and baking soda; cook 3 minutes or until slightly softened. Stir in Worcestershire sauce and thyme. Close and lock lid.  Turn pressure release valve to sealing position.

Cook 20 minutes using high pressure cook setting.  When the timer goes off, use quick pressure release method to carefully release pressure before opening lid.  Add broth; cook 5 minutes using sauté setting on medium heat.

Meanwhile, heat broiler.  Place bread slices in single layer on baking sheet; top evenly with 1/4 C. cheese.  Broil 6 inches from heat, 3 to 5 minutes or until cheese is slightly browned.

Turn off pressure cooker.  Stir vinegar and remaining cheese into soup.  Serve with bread slices.