Heat oven to 400ºF. In food processor, place flour and butter. Cover; process until mixture looks like coarse meal. Add cheese and red pepper. Cover; process, using quick on-and-off motions, until combined. With food processor running, gradually pour water through feed tube; process just until dough forms a ball.
Onto ungreased cookie sheets, drop dough by tablespoonful’s 2 inches apart. Flatten each cookie with bottom of drinking glass; gently press 1 pecan half into center of each cookie.
Bake 12 minutes. Cool 2 minutes; remove from cookie sheets to cooling racks. Store cooled cookies tightly covered.