Roasted Green Beans and Tomatoes with Tahini Sauce

I wanted something slightly different for our Thanksgiving green bean dish.  I know people love the green bean casserole, modernized to use no canned ingredients (well, at least not beyond the fried onions for the top, but I am a bit of a rebel in that department.

I served roasted green beans and grape tomatoes on a bed of tahini sauce.
The beans and tomatoes are tossed with olive oil, salt, and pepper, roasted at 400 degrees in a sheet pan so they are mostly a single layer, and then placed on a thin layer of tahini sauce.  Then grate the zest of one lemon over the top, and serve room temperature.

Tahini Sauce (4 c)
1 head garlic
3/4 c. lemon juice
1 1/2 tsp. kosher salt
2 cups tahini
1/2 tsp. ground cumin

Put unpeeled garlic into blender, add lemon juice and 1/2 tsp. salt, blend.  Pour the mixture through a fine mesh strainer.  Discard solids and add the rest of the ingredients in blender, then add ice water (1-1 1/2 c iced water) until sauce is smooth, thick, and creamy.