Heat the oven to 450 F with rack in the center.

In a cup, combine the honey, vinegar, and crushed red pepper; microwave at full power for 10 seconds, until the mixture is warm enough to stir to blend (repeat if necessary). Reserve the warm honey while preparing the broccoli.

In a shallow 9×13-inch baking dish or a rimmed baking sheet, toss the broccoli spears with oil, then spread in a single layer in the center of the pan. Roast in the oven for 7 to 8 minutes, until broccoli begins to brown on the edges. Remove from oven. Drizzle the hot honey over the broccoli and sprinkle with salt. Scatter the grapes and almonds on top of the broccoli and continue roasting for 4 to 5 minutes until the broccoli is crisp-tender, the almonds are toasted, and the grapes are warmed through.

Transfer the broccoli and grape mixture to a platter or individual plates and serve warm or at room temperature.