Preheat oven to 350°F. Wrap the 6 flour tortillas in foil and place them in the oven to warm while you cook.
Heat a medium skillet over medium heat. Add 1/2 tablespoon canola oil. Add the 1/2 ounce minced ginger and 1 clove minced garlic and sauté, stirring, until fragrant, about 3–4 minutes. Remove the ginger and garlic from the pan and set aside.
Increase heat under the skillet to medium-high. Pat the 10 ounces inside round steak dry with paper towels and season both sides with salt and pepper.
Add the remaining 1 tablespoon canola oil to the hot skillet. Sear the steak 2 minutes per side, until browned. Transfer the steak to a plate and let it rest for 3–5 minutes.
In the same hot skillet, add the 3 tablespoons peanuts and the sliced red bell pepper. Cook, stirring frequently, until the peppers are lightly charred and the peanuts are warmed, about 5 minutes.
Slice the rested steak crosswise into 1/4-inch slices (against the grain). Return the sliced steak and the reserved ginger and garlic to the skillet with the peppers and peanuts; stir to combine.
Stir in 1/2 tablespoon soy sauce, 1 tablespoon hoisin sauce, and 1 teaspoon brown sugar. Add Sriracha sauce and additional salt and pepper to taste. Cook, stirring, until the sauce coats the meat and peppers and everything is heated through, about 1–2 minutes.
Remove the warmed tortillas from the oven. Divide the steak and pepper mixture among the 6 tortillas. Garnish with the 1/8 ounce chopped Thai basil and serve with lime wedges, if using.