It must be a spring thing, but every year about this time, I become obsessed with green sauce. I want it on everything — grilled chicken, poached salmon, steamed cauliflower, my morning cheese toast. Green sauce varies — this spring’s version is slightly Indian — I was going for that great green sauce you get in Indian restaurants but I wound up with something slightly chunkier. Basically, here’s what I did. I took a bunch of scallions out of the bottom of the fridge that were slightly past their time, washed them and trimmed off all the skeevy bits, cut…