Heat oven to 350°F. Line cookie sheets with cooking parchment paper. In medium bowl, mix oats, flour, baking soda and salt; set aside.
In large bowl, beat butter and brown sugar with electric mixer on medium speed 2 to 3 minutes or until light and fluffy. Add eggs and vanilla; beat until blended. On low speed, beat in oat mixture just until blended. Stir in pecans and toffee bits.
Onto cookie sheets, drop dough by heaping tablespoonfuls about 2 inches apart.
Bake 10 to 12 minutes or until light golden brown. Remove from cookie sheets to cooling racks.