Peel potatoes and wash thoroughly. Cut into 1/4-inch thick slices. Pat potatoes dry with paper towels.
In a large nonstick skillet over medium high heat, melt butter and add olive oil. Carefully add potatoes and flip with a spatula until all are evenly coated with butter/oil mixture.
Continue cooking and stirring potatoes, until they get browned and begin to crisp on the edges. Add chopped onion, green pepper, and seasoning. Toss to combine.
Reduce heat and add water to pan. Cover and cook over low heat, until potatoes are tender. (This may take a 10-15 minutes, depending how thick your potatoes are.)
Once potatoes are tender, remove lid and allow water to evaporate. Continue cooking potatoes until edges are crispy again. Serve with ketchup and malt vinegar. Makes 6 to 8 servings. Enjoy!