Fill a large bowl with cold water and swish the radish leaves in it to dislodge any dirt stuck between the leaves. Empty the bowl, repeat the process, and dry the clean leaves between paper towels.
Combine the radish leaves, sunflower seeds, lemon juice, garlic, and parmesan in a food processor or high-powered blender. Drizzle in the olive oil while you pulse/blend the pesto until smooth, about 30-60 seconds. Add more olive oil if needed.
Store in an airtight container in the fridge or freezer. Add to pasta, pizza, eggs, and more, or use as a dip for veggies.
Notes
This will last in the fridge for up to 2 weeks or in the freezer for up to 2 months.
Possible substitutions include pine nuts, pumpkin seeds, or cashews for the sunflower seeds. You can also use beet greens for this recipe.