Preheat a skillet over medium-low heat. Add the oil and the peppers and cook until soft and slightly caramelized, about 10 minutes. Transfer to a plate and set aside.
Form the sausage into 6 equal-sized patties.
Place the sausage patties in the skillet and cook for 4-5 minutes per side until the internal temperature reaches 160 degrees. Top with cheese if desired.
Spread the top and bottom of each slider roll with mayonnaise and mustard.
Place a sausage patty on the bottom half of each bun. Top with peppers and replace the top of the bun.
Notes
If using links, remove the casing before shaping the sausage into patties.