Preheat a 12” or larger heavy-bottomed skillet (cast iron if you have it,) over medium-high heat then drizzle in enough extra virgin olive oil to coat the bottom. Add sausage then saute until lightly browned, 4-5 minutes, then remove to a plate then set aside.
Turn heat down to medium then add enough extra virgin olive oil to once again coat the bottom of the skillet. Add potatoes, season with Old Bay, then saute, stirring occasionally, until potatoes are lightly browned, 10 minutes, adding more extra virgin olive oil if potatoes begin to burn.
Add more extra virgin olive oil to the skillet with bell pepper, onion, and mushrooms then season with more Old Bay. Saute until all the vegetables are tender while stirring occasionally, 20-25 minutes, turning the heat down and/or adding more extra virgin olive oil if needed. Taste along the way, adding more Old Bay and/or salt as needed. Add sausage back into the skillet then stir to reheat.
Meanwhile, heat another large skillet over medium heat then spray with nonstick spray. Cook eggs according to your preference (scrambled, over easy, sunny side up, etc.) then scoop Cajun Hash onto plates and top with eggs.
Notes
If the potatoes are taking too long to soften, place a lid on top of the skillet for 3-4 minutes to speed up the cooking process