Bring about 1 qt. water to a boil in a medium pot. Add 1/2 lb. trimmed green beans and cook until tender to the bite, 3 to 6 minutes. Drain and immerse immediately in ice water until cool, about 2 minutes; drain again.
In a blender or food processor, combine 1 firm-ripe pitted and peeled avocado, 1/2 cup plain nonfat yogurt, 2 tbsp. fresh lime juice, 1 tbsp. loosely packed fresh mint leaves, 1 peeled garlic clove, and 1/2 tsp. kosher salt; whirl until very smooth.
Serve dip with green beans and 1/2 lb. jicama cut into 1/2-in.-thick sticks.
Makes: 1 cup
Time: 30 minutes