On bottom half of wrap, distribute 3/4 cup baby spinach leaves. Then overlap 3 slices of turkey breast on top, leaving a border at bottom edge of wrap. Spread 1 Tbsp. sour cream over turkey. Evenly distribute 1/3 cup sliced mushrooms and 2 Tbsp. roasted pepper strips over turkey. Season with salt and pepper.
Starting with filled side of wrap, roll up gently but tightly into a cylinder, tucking in sides; roll wrap completely. Slice wrap in half diagonally. Repeat with remaining filling and wraps to make 4 cylinders total (or 8 halves).