1. In a saucepan place beet. Add water to cover. Bring to a boil, cover, and simmer until beet is tender, about 35 minutes. Drain and peel beet, then puree in a food processor. Set aside.

2. Preheat oven to 350°F. Lightly oil an 8” square baking dish and line with parchment paper so it extends up 2 sides of pan.

3. In a large microwave-safe bowl combine butter and chocolate. Microwave in 30-second increments, stirring after each, until chocolate is melted and smooth. Stir in sugar, vanilla, and salt. Stir in eggs one at a time. Stir in beet puree. Fold in flour. Scrape batter into prepared baking dish.

4. In a small bowl stir to combine peanut butter and cornstarch. Drop spoonfuls of peanut butter over brownie batter, then use a knife to swirl it into batter.

5. Bake until brownies are set, 30-35 minutes. Let cool in pan for 10 minutes, then use parchment to help transfer brownies to a rack to cool completely before cutting.