Pressure Cook Onions: Heat up Instant Pot using Sauté More function. Wait until it says HOT (roughly 8 mins). Melt 6 tbsp (64g) unsalted butter in Instant Pot. Add ⅓ lb (151g) sliced shallot and 3⅙ lb (1438g) sliced yellow onions in Instant Pot. Add in ½ tsp (2g) baking soda, then mix well. Sauté until onions begin to release moisture (around 5 mins). With Venting Knob in Venting Position, close the lid, then turn Venting Knob to Sealing Position. Pressure cook at High Pressure for 20 minutes, then Quick Release.

Caramelize Onions: Open the lid carefully. There will be a lot of liquid in the Instant Pot. To speed up the process, pour the onion liquid into a large glass measuring cup and reserve it for later. Caramelize the onions by using the 'Saute More' function. Stir occasionally. Once all the liquid has evaporated, turn the heat down to 'Saute Normal'. Saute onions until they are deep golden brown.

Deglaze Instant Pot: Pour in ¼ cup (63ml) Sauvignon Blanc or dry white wine, then completely deglaze the bottom of the pot with a wooden spoon.

Pressure Cook French Onion Soup: Add minced garlic, 1 tbsp (15ml) regular soy sauce, 1 tbsp (15ml) fish sauce, 1 bay leaf, thyme, previously reserved ½ pound (227g) sliced yellow onions, previously reserved onion juice, 4 cups (1L) unsalted beef stock, and 4 cups (1L) unsalted chicken stock in Instant Pot. Give it a quick mix. With Venting Knob in Venting Position, close the lid, then turn Venting Knob to Sealing Position. Pressure Cook at High Pressure for 0 (zero) minutes, then Natural Release for 20 minutes. Then, carefully turn Venting Knob to the Venting position to release the remaining pressure.

Season and Serve: While the Instant Pot is natural releasing, preheat oven to 450°F. Slice French baguette to ¾ - 1 inch thick slices. Optional: Spread melted butter on baguette slices, then toast them in toaster oven. Taste and season the French onion soup with salt. Add French onion soup to an oven-safe bowl. Place a slice of French baguette on top of the soup, then layer freshly grated Gruyère cheese on top. Place the bowls on a baking tray, then place them in a 450°F oven for 6 - 8 minutes, until the cheese melt and browned.