Preheat the oven to 400°F.
Place the sweet potato slices on a baking sheet and toast for 20 minutes, flipping halfway through, until just tender.
Meanwhile, heat the olive oil in a large skillet over medium heat. Add the sausages and brown for 8-9 minutes, turning constantly, until cooked through. Drain on paper towels and transfer to a plate.
Add the bacon to the skillet and cook for 7-8 minutes, flipping constantly, until cooked. Drain on paper towels and transfer to a plate.
Once the sweet potatoes are done, remove them from the oven and lower the heat to 200°F. Place the bacon and sausage inside to keep warm.
Add the tomatoes and mushrooms to the skillet. Cook the tomatoes until the are blistered, turning once, and the mushrooms until they are tender. Transfer to a plate and season with salt and pepper.
Reduce the heat to low and crack in the eggs, adding butter if necessary). Fry as desired.
Divide the sausage, bacon, tomatoes, mushrooms, and eggs between four plates. Butter the sweet potato toast and enjoy.