Prepare the chicken by shredding it into bite-sized pieces if using leftover cooked chicken. If starting from scratch, boil or grill the chicken breast until fully cooked, then let it cool before shredding.

Wash and chop the vegetables: shred the lettuce, dice the tomatoes, and slice the cucumber and bell pepper into thin rounds or strips.

Lay the tortilla flat on a clean surface. Spread the ranch dressing evenly over the tortilla, leaving space around the edges.

Layer the shredded chicken in the center, followed by the lettuce, tomatoes, cucumber, bell pepper, and shredded cheese. Season with salt and pepper.

Fold in the sides of the tortilla and roll it tightly from the bottom up to enclose the fillings. Slice in half diagonally for easy handling.