1. In a large nonstick skillet, heat pine nuts over medium heat until toasted, about 4 minutes. Transfer to a bowl and set aside.
2. Place raisins in a small bowl. Bring 1/2 cup of the water to a boil and pour over the raisins. Set aside.
3. Trim stems from fennel bulb. Remove the fronds from the stems and chop 2 Tbsp. Discard stems and any remaining fronds.
4. Cut bulbs in half. Cut out the cores, then slice fennel into 1/4-inch-thick slices. Add to a large nonstick skillet or saucepan with remaining 1/4 cup water and oil. Bring to a boil over medium-high heat. Cover pan and cook, shaking the pan occasionally, until fennel is just barely tender, about 3 to 4 minutes.
5. Uncover, add onion, and continue to cook, stirring occasionally, until the liquid evaporates and the fennel begins to sizzle in the oil, about 2 minutes. Drain the raisins, discard the soaking liquid, and add to fennel.Continue to cook, stirring constantly, until fennel is tender, about 2 to 4 minutes longer. Add vinegar, salt, pepper, toasted pine nuts, and reserved fennel fronds, and toss to distribute. Transfer to a platter and serve immediately.
Source: Fresh Magazine September, October 2010