1. Season flank steak with 1/2 tsp. salt and 1/2 tsp pepper.
2. Heat 2 TBSP oil in heavy 5-6 quart pot, over medium high heat. Add half of sliced steak to pot in a single layer and cook until well browned, about 2 minutes per side. Transfer steak to a plate. Pour off any oil in pot and repeat with another 2 TBSP oil and remaining steak.
3. In the same pot, heat 1 TBSP oil over medium-high heat. Add quartered onion, half of green pepper, and half of yellow pepper. Cook, stirring frequently, until vegetables are lightly browned, about 5 minutes.
4. Add chicken broth, bay leaves, peppercorns, cumin and 1/4 TSP salt. Add cooked steak and any juices on the plate. The steak should be just covered with broth; pour in additional broth if necessary. Bring to a boil; reduce heat to low and simmer, covered, until steak is fork-tender; about 2 1/2 hours. Remove pot from heat and let steak cool in broth for 30 minutes.
5. Transfer steak to a plate. Strain cooking liquid through a sieve set over a bowl; discard solids. Let liquid stand 5 minutes, then skim off and discard any fat. Set cooking liquid aside. Shred steak.
6. In the same pot, heat 2 TBSP oil over medium heat. Add thinly sliced onions, remaining green and yellow peppers, red pepper, garlic, 1/2 TSP salt, and 1/4 TSP pepper. Cook, stirring frequently, until onions and peppers soften, 15 to 20 minutes.
7. Stir in tomato paste until vegetables are coated. Stir in crushed tomatoes with their juice, 2 1/2 cups of the reserved cooking liquid, and 1/4 TSP salt. Bring to a boil; reduce heat to low and simmer until slightly thickened, about 20 minutes.
8. Return shredded steak to stew and cook until heated through. Stir in olives. Taste and adjust seasoning. Serve with black beans and white rice.
