Larabar's Founder Stocked Shelves at Whole Foods to Learn About Retail By starting at the bottom, Lara Merriken got a quick education to food-product sales and marketing.

Lara Merriken needed to make some changes. In 2000, after an intense decade spent earning a psychology degree and building a career in social work, she could no longer ignore her entrepreneurial itch. She thought about how her own wheat allergy had forced her to rethink her diet -- and to find her own solutions. What began as kitchen experiments to benefit her own health eventually grew into Lärabar, a snack brand that launched in 2003 and won over fans with its dessert-flavored bars (cashew cookie, cherry pie) made from a handful of natural, whole ingredients. Merriken's commitment to keeping her products simple became her biggest asset, and when she sold Lärabar to General Mills in 2008, it was because she trusted the food giant to stay true to that ethos. Today, Lärabar has five product lines, and Merriken still serves as creative director, helping to ensure that the brand continues to grow in the same way she built it: One step at a time.

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1. Solve your own problem.