Preheat oven to 400 degrees F. Grease a 2 1/2-qt. baking dish with some oil.

Cut stalks off fennel and quarter bulbs lengthwise. Cut out and discard cores and very thinly slice fennel. In a 10" skillet, heat oil over medium. Add onions and fennel. Season with salt. Cook until tender, stirring occasionally, 8 to 10 minutes. Cool slightly.

Meanwhile, to a microwave-safe medium bowl, add butter. Cover with vented plastic and microwave until melted, 1 to 2 minutes. Whisk in half & half until smooth. Season with salt and pepper.

Peel and very thinly slice potatoes. In prepared dish, arrange 1/3 of potato slices in even layer. Top with 1/3 of fennel mixture. Pour 1/3 of half & half mixture on top. Sprinkle with 1/2 cup Gruyere. Repeat layering twice more.

Coat a piece of foil with cooking spray and cover the gratin. Bake 30 minutes. Remove foil and continue baking until potatoes are tender when pierced with a knife and top is golden brown, 20 to 25 minutes. Let stand 15 minutes before serving.

Tip: Use a mandoline or food processor with slicing attachment to slice potatoes quickly and evenly.

Source: Hannaford fresh Magazine, October November 2024