Layer in a 1-quart glass jar or canister the following ingredients: oats, nuts, brown sugar, cinnamon, chocolate pieces, biscuit mix, cherries or raisins, and sunflower seeds. Tap jar gently on the counter to settle each layer before adding the next one. Cover jar.
Store at room temperature up to 1 month. Or, attach baking directions and give as a gift.
Heat oven to 375 degrees F. Grease an 8x8x2-inch baking pan. Empty contents of jar into a large bowl. Add egg, milk, oil, and vanilla. Stir until combined. Spread into prepared pan. Bake for 25 minutes or until edges are brown. Cool in pan on a wire rack. Cut into bars.