Heat olive oil in a saucepan over medium-low heat. Cook onion and green bell pepper in hot oil until softened, about 5 minutes; add garlic and cook another 3 minutes. Stir water, black beans, rice, cumin, salt, and paprika with the onion mixture; add bay leaf. Bring the liquid to a boil, cover saucepan with a tight-fitting lid, reduce heat to low, and cook until the rice is tender and the moisture is absorbed, 50 to 60 minutes. Remove and discard bay leaf.
While rice cooks, mix mango, red bell pepper, green onion, cilantro, jalapeno pepper, lime juice, and olive oil together in a large bowl; refrigerate at least 30 minutes.
Heat a large skillet over medium-high heat. Cook and stir beef with chili powder, cumin, garlic powder, onion powder, red pepper flakes, oregano, and paprika in the hot skillet until browned and crumbly, 5 to 7 minutes; drain and discard grease.
Stir mango salsa before serving along with the black beans and rice, seasoned ground beef, tortillas, and your preferred taco fillings.