Preheat your oven to 400°F. Pierce the sweet potato with a fork and roast it until tender, about 45 minutes, or until soft when pressed.
Meanwhile, season the chicken breast with salt and pepper and grill it over medium-high heat until fully cooked, about 6-7 minutes per side. Once done, set aside and slice thinly.
Once the sweet potato is roasted, let it cool slightly. Scoop out the flesh and mash until smooth.
In a bowl, combine the mashed sweet potato with whole wheat flour and the egg. Mix until a dough forms. If the dough is too sticky, sprinkle in a little extra flour.
Divide the dough into sections and roll each into a long rope on a floured surface. Cut the ropes into 1-inch pieces to form the gnocchi.
Bring a pot of lightly salted water to a boil. Add the gnocchi and cook until they float to the surface, about 2-3 minutes. Remove with a slotted spoon and set aside.
In a small saucepan over medium heat, melt the unsalted butter. Add the fresh sage leaves and let the butter cook until it turns a light brown color and gives off a nutty aroma. Be careful not to burn the butter.
Toss the cooked gnocchi in the sage brown butter and season with additional salt and pepper if needed.
Plate the gnocchi and top with the sliced grilled chicken. Serve immediately and enjoy the blend of fresh herb notes, nutty brown butter, and the wholesome heartiness of sweet potato gnocchi.