Preheat oven to 375F, Line a rimmed baking sheet with parchement paper and cover with thinly sliced onion. Set aside.
Meanwhile, cook mushrooms in butter in medium sized skillet until wilted and liquid evaporates. Season with salt and pepper.
Place turkey breast skin side down on prepared baking sheet. Season with salt and pepper.
Combine mushrooms, goat cheese, rosemary, and marmalade. Spread on turkey breast. Roll jelly roll style and tie with kitchen twine or use metal skewers to secure filling. Turn so that it is seam side down.
Combine glaze ingredients and brush over turkey.
Cook in preheated oven 60-65 minutes or until it reaches an internal temperature of 165°F Remove from oven, cover with foil and let sit for 10 minutes before slicing.
TIPS: Please show some slices, sliced on diagonal, as well as remaining whole turkey breast.