Lightly spoon flour into dry measuring cups; level with a knife. Combine flour, baking powder, and 1/4 teaspoon salt; stir with a whisk.
Combine sugars, butter, and shortening in a large bowl; beat with a mixer at medium speed until light and fluffy, about 3 minutes. Combine 1/4 cup water, egg substitute, Kahlúa, and vanilla in a small bowl. Add Kahlúa mixture to sugar mixture; beat 2 minutes or until well blended. Gradually add flour mixture; beat at low speed just until combined. Fold in chocolate chips, white chocolate chips, and pecans. Drop by level tablespoonfuls 2 inches apart onto ungreased baking sheets. Bake, 1 sheet at a time, at 350° for 14 minutes or just until set and beginning to brown around edges and on bottoms. Remove from oven; cool on pan 1 minute. Remove from pan; cool completely on wire racks.
Note: You can freeze completely cooled cookies for up to a month in a zip-top plastic bag.