Thoroughly clean ramps. Separate green leaves from white/ pink roots. Roughly chop.
1 bunch wild ramps
Place a saute pan over medium high heat, toast the walnuts 3 to 5minutes. Keep a close eye, walnuts go from toasty to burnt quickly. Add toasted walnuts to blender or food processor. Give it a quick whirl to to break up the pieces.
⅓ cup chopped walnuts
Return pan to stove, reduce heat to medium. Add 1-2 tablespoon of walnut oil to the pan. Add green and white ramp parts, saute 3 to 5 minutes until soften. Move to blender.
1 bunch wild ramps, ½ cup walnut oil, divided
Add green ramp leaves, lemon juice, cheese, and pinch of salt to blender. Pulse to combine. Slowly add the walnut oil while blending on high speed. Start with a ⅓ cup of walnut oil and add more, if needed, to get to desired consistency.
½ cup walnut oil, divided, 2 teaspoon lemon juice, ¼ cup parmesan cheese, kosher salt and pepper
Adjust salt, pepper and lemon juice to taste.
Notes
It is optional to blanch the green ramp leaves. I only do this if I am making the pesto ahead of time and want to ensure it stays vibrant green.
Sauteeing the wild ramps is an optional step but I find it brings out a bit of the natural sweetness.