Poached Eggs With Asparagus with balsamic

8 eggs 200 g field salad greens (mache, corn salad) 1 1/2 liters water 3 tablespoons vinegar 30 g butter 1 onion , chopped 4 tablespoons concentrated tomato[...]

4 portabella mushroom caps , stems discarded (3-inch-wide) 2 plum tomatoes , halved lengthwise 3 tablespoons olive oil 1/2 teaspoon salt 1/4 teaspoon black[...]