In a large mixing bowl combine 1/3 cup flour & 1 tsp seasoned salt, whisking together until evenly combined.
Add the beef to the flour mixture and toss to coat. Shake off any excess and transfer coated beef to a waiting plate. Set aside.
Add the oil to a skillet set over medium heat. When hot (shimmery), carefully add the coated beef to the pan.
Allow the beef to cook, stirring occasionally, just until seared. This will only take about 2 minutes. You don't want the beef to cook through.
Lightly spray the bowl of your crockpot with nonstick cooking spray, then transfer the seared beef to it.
Add the peppers, garlic, and ginger paste to the skillet- plus extra oil, if needed. Sauté for 3-5 minutes, just until the peppers begin to soften.
Add the tomatoes (including juice), beef broth, Worcestershire, and soy sauce to the skillet. Stir everything together to combine, and bring the mixture to a simmer.
Whisk in 1 tablespoon of flour to the tomato & pepper mixture until evenly combined. Pour this mixture over the beef in the crockpot.
Cover & cook on low for 6-8 hours, or on high for 4 hours.
When there's only 30 minutes of cook time left, whisk together 1 1/2 tbsp of cornstarch & 1 tbsp water to form a slurry. Stir the slurry into the crockpot, cover, and continue cooking.
Serve the crockpot pepper steak over steamed white rice. Enjoy!