Preheat your oven to 400°F (200°C).
Dice the baby potato into 1-inch cubes, slice the bell pepper into strips, and thinly slice the red onion.
In a bowl, toss the diced potatoes, bell pepper, and red onion with olive oil, chopped rosemary (reserve some whole for garnish if desired), salt, and pepper.
Transfer the vegetables onto a baking tray in an even layer and roast for 20-25 minutes until tender and slightly crispy.
While the vegetables roast, slice the turkey sausage into bite-sized pieces and lightly pan-sear in a non-stick skillet over medium heat until browned, about 3-4 minutes.
In a separate bowl, beat the eggs with a pinch of salt and pepper.
Once the vegetables are roasted, lower the oven temperature to 375°F (190°C), stir in the sausage pieces, and then make a few small wells among the ingredients.
Pour the beaten eggs into the wells, allowing them to set and bind the ingredients as they bake for another 8-10 minutes until the eggs are fully cooked.
Remove from the oven, garnish with additional rosemary if desired, and serve warm.