Whisk until smooth. You may need to add more water to get to a saucy consistency.
Make the Green Beans:
Heat 2T of olive oil in a pan over medium heat.
Add half of the green beans and saute' until brown, blistered, and wrinkled in spots.About 6 minutes.
Add garlic and continue to saute' until lightly brown.
Add half of the rosemary and parsley, along with a touch of salt to combine.
Transfer to a platter and then repeat with the rest of the green beans.
Drizzle the green beans with the dressing. Grate some lemon zest over the top.
Notes
For the best blistered texture, cook the green beans in batches so the pan does not become overcrowded. If too many beans are added at once, they will steam instead of brown. Haricots verts cook especially well here because they blister quickly while staying crisp-tender.Tahini brands vary quite a bit in thickness, so add warm water a little at a time until the sauce reaches a smooth, drizzleable consistency. Fresh lemon juice is strongly recommended because it keeps the sauce bright and balanced.Store leftovers in an airtight container in the refrigerator for up to 2–3 days. Reheat gently in a skillet or low oven to help maintain the texture of the green beans.