Cream shortening in a large mixing bowl; gradually add sugar, beating well. Add eggs, one at a time, beating well after each addition.
Sift together flour, baking powder, soda, and salt in a medium mixing bowl; add cereal and pecans, stirring to coat well. Stir flour mixture and vanilla into creamed mixture, mixing well.
Drop dough by teaspoonfuls 2 inches apart onto greased and floured cookie sheets. Bake at 325° for 10 to 12 minutes. Remove from cookie sheets, and cool on wire racks.