Step 1

Place 1 1/2 to 2 pounds boneless beef chuck roast in a large bowl and add enough cold water to cover. Let sit for 30 minutes. Meanwhile, dice 1 large yellow onion (about 2 1/2 cups). Peel and mince 1 medium head garlic (about 1/3 cup).

Step 2

Drain the beef and rinse under cold water. Trim off any large pieces of surface fat. Place in a 6-quart or larger Instant Pot or electric pressure cooker. Add enough cold water to cover the beef by about 3 inches. Add 3/4 of the onion, 3/4 of the garlic, and 2 teaspoons kosher salt.

Step 3

Lock the lid on and make sure the valve is set to seal. Set to cook for 40 minutes under HIGH pressure. It will take about 30 minutes to come up to pressure.

Step 4

Meanwhile, peel and dice 1 pound Yukon Gold potatoes (about 3 cups). Trim and quarter 2 medium zucchini lengthwise; cut crosswise into 1/2-inch pieces (about 3 1/4 cups). Cut 2 of the medium scallions crosswise into 1-inch pieces; thinly slice the remaining 1 medium scallion and reserve for garnish. Thinly slice 1 green Korean pepper or 1 small jalapeño pepper crosswise if using. Drain 1 (about 14-ounce) box firm tofu; cut the tofu horizontally into 4 slabs, then cut the slabs into 1/2-inch pieces.

Step 5

When the cook time is up, you can quick release the pressure, or preferably, naturally release the pressure. Transfer the beef to a bowl with tongs.

Step 6

Turn the pressure cooker to the highest Sauté setting and bring the broth to a simmer. Add the potatoes and cook for 5 minutes. Add the remaining onion and garlic, zucchini, and 3/4 cup doenjang. Stir to combine and cook for 10 minutes. Meanwhile, shred the beef into bite-sized pieces when cool enough to handle, discarding any sinew or fatty parts.

Step 7

Add the beef, green pepper if using, tofu, and 1-inch scallion pieces. Gently stir to combine and cook for 5 minutes. Taste the soup and add more doenjang or salt as needed. Serve garnished with the thinly sliced scallions and gochugaru flakes.