Creating One Pan Kielbasa and Potatoes is as simple as following these steps:

1. Preheat the Oven: Preheat your oven to 400°F (200°C).
2. Prepare the Ingredients: Wash and dice the potatoes, chop the bell pepper, and slice the onion. Set aside.
3. Mix Seasonings: In a large bowl, combine olive oil, garlic powder, paprika, black pepper, and salt. Stir well.
4. Combine Ingredients: Add the sliced kielbasa, diced potatoes, chopped bell pepper, and sliced onion to the bowl. Toss until all ingredients are well-coated with the seasoning mixture.
5. Arrange on Baking Sheet: Spread the mixture evenly onto a large baking sheet or in a roasting pan. Ensure everything is in a single layer for even cooking.
6. Bake: Place the pan in the preheated oven and bake for about 30 minutes. Stop halfway to stir and rearrange the ingredients for golden browning.
7. Check for Doneness: The dish is ready when the potatoes are fork-tender and the kielbasa is slightly crispy.
8. Garnish: Remove from the oven and sprinkle with freshly chopped parsley, if desired, before serving.

These steps should guide you easily through this incredible dish.