Whisk together ingredients for the dressing and set aside.
To blanch your asparagus, bring a large pot of water to a boil with a generous sprinkle of salt—a heaping 1/4 cup. When the water comes to a boil, add the asparagus and boil for 3-5 minutes, depending on the size of the stalk (thinner= less time, thicker= more time). Prepare a bath of ice water.
When asparagus is bright green and tender—but still crisp--drain and transfer to the iceboat to stop the cooking. When the stalks have cooled, drain and set out on a towel to dry.
To assemble, toss the asparagus and fennel together and plate on a serving platter. Sprinkle with feta, olives, and a sprinkle of salt and pepper. To serve, drizzle with the dressing and a squeeze of fresh orange juice.