Heat oven to 375°F. Spray 20 mini muffin cups with cooking spray.
In 12-inch skillet, heat oil over medium heat. Cook sausage in oil 5 to 8 minutes, breaking up sausage with spoon, until browned. Add corn and broth. Cook 3 minutes, stirring occasionally, until sausage is thoroughly cooked and corn is heated.
Remove pie crusts from pouches; unroll on lightly floured work surface. Using 2 1/2-inch round cookie cutter, cut 10 rounds from each crust. (Reroll scraps and cut additional rounds, if desired.) Brush rounds with egg.
Fit rounds into muffin cups, pressing in gently and crimping any overhanging dough. Divide chorizo mixture evenly among tart shells. Lightly brush edges with egg.
Bake 10 to 15 minutes or until golden brown. Top each tart with sour cream and chives. Serve warm.