Slice off the root end and trim the stalks and feathery fronds of the fennel bulbs. Cut the bulbs into halves, remove and discard the tough inner cores, and slice thin.
In a large skillet, saute the garlic and fennel in the oil on medium-high heat for about 7 minutes, stirring frequently and adding a splash or two of water if necessary to prevent sticking, until the fennel is golden brown.
Add the ginger and the orange juice, cover, lower the heat, and simmer until the fennel is tender, about 5 minutes.
Sprinkle on the sugar and salt and pepper to taste. Serve garnished with reserved fennel fronds.