Combine biscuit mix, oats, and pecans; set aside.
In a mixing bowl, cream butter and sugar until light. Beat in eggs, one at a time, beating after each addition. Stir in mashed bananas and milk. Add dry ingredients all at once, stirring just to moisten. Turn into a greased and floured 9x5x3-inch loaf pan. Bake at 350° for 40 to 45 minutes, or until a wooden pick or cake tester inserted in center comes out clean.