Prepare cake (the cake is best prepared the day before. Wrap and store overnight).
Place rack in center of the oven, preheat to 350ยบ F. Lightly oil a 9 x 5 inch loaf pan, dust with flour, shaking out any excess. Set pan aside.
In large bowl, whisk together eggs, sugar and salt; mix until foamy and smoothly blended. Whisk in grated zest.
Spoon flour and baking powder into a sifter (if you don't have a sifter, use a fine mesh colander or strainer); sift about a third into the eggs' whisk lightly until combined, do not beat. Continue two more times; sifting flour into the batter and whisking until just incorporated. Whisk in heavy cream; then oil.
Pour batter into the prepared pan; bake 50 - 60 minutes, or until toothpick inserted into center comes out clean. Remove to a cooling rack; allow to cool 10 minutes before unmolding. Cool to room temperature, right side up, on the rack. When cool, wrap with plastic wrap if allowing to sit overnight. Makes 10 - 12 servings.
Wash and cut fruit half. Remove pits.
Combine honey, vinegar and vanilla in small bowl. Mix Well.
Prepare grill to medium. Be sure to clean it well of any cooked matter as you don't want your dessert tasting of dinner
Slice cake into slices. Place on grill and grill, turning once or twice, until lightly toasted.
Place fruit on the grill, cut side down. Grill for a few minutes, turn, brush with glaze; grill, turning and basting cut side with glaze until the fruit is tender, but still firm, and cut side is golden and caramelized (take care it does not burn, honey likes to burn). Once cooked, remove to a cutting board and slice the fruit.
Arrange fruit on slices of toasted cake. top with whipped cream, ice cream or yogurt. Sprinkle with a bit of coarse salt, if desired.