Cut each potatoes in half, then in half again. Slice the quarters in half. You’ll have 8 pieces per potato.
Place the butter in a small microwave-safe dish. Microwave on high until melted, about 20–30 seconds. Stir in the olive oil, grated garlic, Italian seasoning, and salt (to taste).
Place the potato slices on a sheet pan with a small rim. Pour the butter and olive oil mixture over the top. Toss gently with your hands. Spread the potato slices evenly on the baking sheet, leaving space between each slice (this will ensure that the potatoes get crispy—crowding the potatoes will make them steam instead of crisp up).
Bake for 20 minutes. Toss the potatoes and return to the oven for another 15–20 minutes, or until the potato slices are crispy and cooked through. Serve immediately.
Notes
Tip: grate the garlic finely on a microplane (here's the one I use) so it doesn't burn in the oven!