Preparation Steps

• Preheat oven to 475°F (use convection if you have it). Line a half-sheet pan with foil if desired for easier cleanup. Add the potatoes, evenly drizzle with olive oil, toss with your hands to combine, and flip all potatoes so the cut-side is down.
• Add the onion wedges, evenly spaced throughout the potatoes. Tip: Do not cut these smaller than a 1-inch thick wedge or they will be prone to burning. Try to keep them in a 'stack' of onions rather than individual onion pieces which will also be prone to burning. Evenly drizzle each onion stack with a touch of olive oil.
• Evenly sprinkle 2/3 of the packet of seasoning mix over the potatoes and onions. It looks like a lot, but it's fine.
• Evenly season with pepper.
• Roast for about 25 minutes, or until the potatoes are beginning to turn lightly golden brown on the cut-side-down sides.
• Flip all the potatoes and onions. Evenly drizzle with a bit more olive oil if things look at all dry, return to the oven, and roast for about 7 more minutes.
• While the potatoes and onions finish roasting, add the butter to a small skillet and heat over medium-high heat to melt.
• Stir in the panko and the remaining 1/3 packet of ranch mix.
• Remove the sheet pan from the oven, and evenly spoon the panko mixture over the potatoes and onions.
• Return sheet pan and roast for an additional 7 minutes, or until lightly golden browned on top. Keep a very close eye on things at this point so you don't burn the topping. Start checking very closely after 5 minutes.
• Evenly sprinkle with Parmesan, optional parsley, and serve immediately.