Cut the turkey skin around the leg quarter using a sharp knife, then slide the knife under the bone to free the meat.
Cut the joint between the thigh and leg and remove the thigh bone—Reserve thigh bones for gravy.
Mix half a teaspoon of sage, salt, and ¼ teaspoon of pepper in a bowl. Rub each thigh using your hands. Refrigerate each leg quarter for 6 to 12 hours on a plate.
Heat the oven to 300 °F and set wire racks. Spread cubed bread on a wire rack on baking sheets, and bake until they are lightly browned and crispy for 25-30 minutes. Transfer dried and crispy bread to a large bowl.
Now add cranberries and eggs to the bread and toss to combine. Transfer the bread stuffing to a skillet and use a rubber spatula to pat the stuffing.
Melt butter sticks in a non-stick oven-safe skillet, add chopped onions and cook, occasionally stirring, until translucent for 10-12 minutes.
Add diced celery, sage, and pepper. Cook until the celery is slightly softened. Transfer veggies to a bowl with crispy bread.
Put marinated turkey breast in a skillet and roast in the oven for 30 minutes.
Once roasted, place it over the stuffing, brush with oil, and season with salt. Transfer the turkey to the oven and roast for 30 minutes.
Transfer the roasted breast to a plate and rest for 30 minutes.
While the turkey rests, using a metal spatula, scrape the browned bits. Before serving, season stuffing with the bits. Carve and serve.