We grill them in foil packets. I don't blanch first, but you could. We usually drizzle w/ olive oil, salt, pepper and garlic or shallots, seal the foil packet and toss it on the grill w/ whatever else we are making. I would say 15-ish min maybe. Otherwise I typically steam them for 10-ish minutes, just until the color turns vibrant. I don't blanch them first for steaming, either, but I don't like my beans mushy, I like them to maintain a little crisp. My MIL makes a good potato salad that has green beans in it, along with red onion, potatoes, and she uses a balsamic vinegar and oil based dressing. It's nice for summer.