Heat oven to 350°F. In 8-inch square pan, bake pecans 6 to 8 minutes, stirring occasionally, until light brown. Spread nuts on cutting board; cool 5 minutes. Finely chop.
In large bowl, beat butter and brown sugar with electric mixer on medium speed, scraping bowl occasionally, until fluffy. Beat in 1/2 teaspoon maple flavor and the egg until well blended. Stir in flour and chopped toasted pecans.
Shape dough into 1-inch balls. On ungreased cookie sheets, place balls 2 inches apart. Flatten in crisscross pattern with fork dipped in granulated sugar.
Bake 11 to 14 minutes or until edges just begin to brown. Cool 1 minute; remove from cookie sheets to cooling racks. Cool completely, about 10 minutes.
In small bowl, mix icing ingredients until smooth; drizzle over cookies.