Roasted potatoes in olive oil is nothing new, but I've been enjoying this technique passed on by a friend recently. The key is to not layer or crowd the potatoes: you want them to roast, not steam. I love the combination of the caramelized sweet potatoes and the savory red potatoes.
Roasted Reds and Sweets
2 medium sweet potatoes, scrubbed
2-4 medium/large red potatoes, scrubbed
3-4 T. olive oil
salt and pepper
1/2 t. thyme
Cube potatoes into one-inch squares. Spread out on a rimmed cookie sheet sprayed with non-stick spray. Drizzle olive oil over the potatoes and toss to coat evenly. Sprinkle salt, pepper, and thyme over the potatoes.
Roast at 425 for 50-60 minutes, tasting to check tenderness.