01 -
Using a sharp knife, thinly slice the flat iron steak against the grain.
02 -
Remove the tops, ribs, and seeds from both bell peppers and slice them thinly. Remove the outer layer and ends from the onion, then slice thinly or separate into petals.
03 -
Transfer the sliced steak, red bell pepper, green bell pepper, and onion to the slow cooker insert.
04 -
In a small bowl, combine tapioca flour with 2 tablespoons of cold water and whisk until smooth.
05 -
Add garlic paste, ginger paste, soy sauce, beef broth, honey, and ground black pepper to the tapioca mixture. Whisk until thoroughly combined.
06 -
Pour the prepared sauce mixture over the steak and vegetables in the slow cooker and mix lightly to coat.
07 -
Cover the slow cooker and cook on high for 3 to 4 hours or on low for 6 to 9 hours, until the steak is tender and the sauce is thickened.
08 -
Serve the pepper steak hot, accompanied by rice or noodles if desired.