The organic purist, eco-conscious, thigh-conscious and dietary trendy may rejoice that Rick's Dessert Diner on K Street has a new neighbor with a new selection of baked treats. Sugar Plum Vegan, a vegan and wholesale bakery that offers fair-trade coffee and organic ingredients, has opened its doors for service. The cozy spot, situated below what was True Love Coffeehouse, has just enough capacity to hold five small tables and a very friendly staff, unfazed by transition issues with the ATM and continuous stream of customers placing to-go orders. "We want those that are hard core vegans as well as those who are just curious to feel comfortable here" said Owner and Chef, Melissa Sugar. T