Place currants and 1/2 cup hot water in a bowl. Cover and let stand 20 minutes or until soft. Drain currants.
Lightly spoon flour into a dry measuring cup; level with a knife. Combine flour and next 4 ingredients (through salt) in a medium bowl. Combine ricotta and eggs, stirring with a whisk; stir in currants. Add ricotta mixture to flour mixture, stirring just until moist.
Spoon batter into 24 miniature muffin cups coated with cooking spray. Bake at 350° for 20 minutes or until a wooden pick inserted in center comes out clean. Remove from pans immediately; place on a wire rack. Serve warm.