In the same bowl that the sauce was in whisk together the arrowroot powder or cornstarch with a teaspoon of water until it's smooth. Pour it into the bean mixture and stir together until combined.
Cover the pan with a lid and simmer over low heat for another 5-7 minutes or until the sauce has thickened and the beans are heated through.
Taste for seasoning then serve on whole wheat or gluten-free slider rolls topped with dill pickle chips, lettuce and tomato.
The sloppy Joe mixture can be made 1-2 days in advance if needed and reheated on the stove or in the microwave. Just like with chili, they taste even better the next day.