Set a medium skillet over medium-low heat. When pan is warm, add 2 tablespoons olive oil, onions, and a pinch each salt and pepper. Once you hear the faintest sizzle, edge heat down to low. Cook 50 - 60 minutes, stirring every 10 minutes or so. Add more olive oil as needed and adjust heat lower if onions start to brown on the edges. Toward the end of cook time, add more salt to taste. Set aside to cool, set aside a few caramelized onions for garnish, then chop the rest of the carmelized onions.

Meanwhile, set whole potatoes in a large pot filled with cold water and bring to a boil. Once boiling, add 3 tablespoons salt. Cook potatoes in boiling water for 12 - 18 minutes, or until fork tender. Set potatoes aside until cool enough to handle, then cut potatoes into 1-inch pieces.