Scrub potatoes while running under cold water, if needed, before cutting into halves or quarters. Combine sliced potatoes and 1 Tbsp kosher salt in a medium saucepan; add enough water to cover potatoes plus 1″. Bring water to a boil, then reduce heat, and simmer until potatoes are tender, 20–25 minutes; drain water from potatoes and pat dry.
Heat butter in a large skillet over medium-high heat. Add the cooked potatoes; season with Kosher Salt and Smoked Peppercorn Sage Rub. Cook, tossing occasionally, until golden brown and crisp, 8–10 minutes. Serve topped with Sea Salt.