In salted, boiling water, cook kale until wilted, 5 minutes. Drain, let cool and squeeze dry; chop. In medium bowl, mix kale, ricotta, eggs and flour with 1/2 tsp. salt and 1/4 tsp. pepper. Form into 1 1/2-inch balls; roll in panko. In skillet, heat oil over medium-high. Fry balls, turning often, until golden all over, about 4 minutes. In small bowl, mix sour cream and pesto for dip.