Preheat your oven to 425°F (220°C) and prepare a half sheet pan with parchment paper. Wash and scrub the potatoes, then cut them in half lengthwise.

Drizzle the potatoes with olive oil, season with salt and pepper, and roast cut side down for about 15 minutes until golden brown.

Add the sliced red spring onions over the potatoes and continue roasting for an additional 25 minutes until tender and caramelized.

Remove from oven and let cool for about 10 minutes.

In a large bowl, mix fresh arugula, sliced radishes, and reserved onion stems.

In a food processor, combine arugula, basil, chives, garlic, and pine nuts. Pulse until finely chopped. Add cheese, lemon zest, juice, and honey. Slowly drizzle in olive oil while blending until smooth; season with salt and pepper.

Combine the roasted potatoes and onions with the arugula mixture. Drizzle the pesto over and gently toss until well coated without mashing the potatoes.

Serve your salad warm or at room temperature, garnished with extra black pepper or cheese if desired.