1 tbsp canola oil grapeseed oil, or a different neutral oil
2 lbs sirloin cut into 2-inch, by ½-inch strips
2 tsp garlic powder
1/2 tsp black pepper
½ tsp kosher salt
1 large yellow onion
2 green bell peppers cored and cut into ½-inch strips
¼ c. plus 2 tbsp water, divided
1 15-oz. can fire-roasted diced tomatoes in their juices
¼ c. low sodium soy sauce plus additional to taste
2 tbsp honey
2 tbsp Worcestershire sauce
1 tbsp minced fresh ginger
2 red, yellow, or orange bell peppers cored and cut into ½-inch strips
5 tbsp cornstarch divided
Prepared brown rice quinoa or cauliflower rice, for serving
¼ tsp red pepper flakes plus additional to taste
Step 1: In a bowl, place the beef and sprinkle with garlic powder, salt, and black pepper. Toss to coat the beef well.
Step 2: In a large skillet, heat the oil over medium-high heat. Add the beef to the hot oil and cook for about 5 minutes on all sides or until the beef is lightly brown. To a 6-quart slow cooker, transfer the beef along with any cooking juice.
Step 3: Add the onions to the same skillet. Adjust the heat to high, then carefully pour in 1/4 c. water. Stir to scrape the browned bits from the bottom of the pan. Cook the onions for about 3 minutes until the onions start to soften, turned slightly brown, and the liquid has cooked off. Shift the onion to the slow cooker.
Step 4: Add the green and red bell peppers to the slow cooker along with the tomatoes. Whisk the soy sauce, Worcestershire sauce, honey, ginger, red pepper flakes, and 3 tbsp cornstarch in a small bowl or a large liquid measuring cup until well combined. Then, pour into the slow cooker.
Step 5: Cover the pot and set to cook for 6 to 7 hours on low or 3 to 4 hours on high or until the beef is tender.
Step 6: Mix the rest of the 2 tbsp cornstarch with the rest of the 2 tbsp water in a small bowl to make the slurry. Stir this into the slow cooker. Turn the slow cooker to high and cook for additional 10 minutes, uncovered, until the mixture has thickened. Stir again and adjust the salt, soy sauce, and/or red pepper flakes according to taste.
Step 7: Serve the pepper steak immediately over brown rice and garnish it with green onions. Enjoy!