Heat oven to 350 degrees. Grease two 8-by-4-inch loaf pans. In large bowl, combine oat flour, baking soda, cinnamon, nutmeg and salt.
In large bowl using mixer, beat butter and sugar until light and fluffy. Beat in eggs one at a time. Add vanilla, oat flour mixture and pumpkin; beat until just blended.
Stir in walnuts and chocolate chips. Spoon mixture into prepared pans. Bake 50-55 minutes, or until toothpick inserted in center comes out clean. Cool 10 minutes. Remove from pan. Cool completely.
In small bowl, stir confectioners’ sugar and milk until smooth. Drizzle mixture over pumpkin bread.