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Butternut Squash Flan with Parmesan Sage Sauce

This elegant butternut squash flan is a sophisticated vegetarian dish that celebrates the natural sweetness of roasted squash. The silky, custard-like texture of the flan is beautifully balanced by a rich, savoury parmesan and sage sauce, making it a wonderful centrepiece for a seasonal lunch or an impressive dinner party starter. Roasting the squash first intensifies its earthy flavour, which pairs traditionally well with the aromatic, peppery notes of fresh sage leaves.

Providing a lighter alternative to a traditional quiche or tart, this crustless flan is naturally gluten-free if checked against specific ingredient labels. It is an excellent choice for those seeking a comforting yet refined homemade meal. Serve it in generous wedges with a crisp green salad or warm crusty bread to soak up the luxurious cream sauce for a truly satisfying vegetarian feast.

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Ingredients for Butternut Squash Flan with Parmesan Sage Sauce

  • 1 (1.1kg) butternut squash, halved lengthwise and seeded

  • 4 large eggs plus 2 yolks

  • 475ml half-and-half

  • 30g finely grated Parmigiano-Reggiano (1/2 cup plus 2 tablespoons )

  • 4 large fresh sage leaves plus 2 teaspoons finely chopped sage

  • Garnish: fresh sage leaves

  • a candy or instant-read thermometer

How to make Butternut Squash Flan with Parmesan Sage Sauce

Put oven rack in middle position and preheat oven to 204°C.

Roast squash, cut sides down, in a lightly oiled shallow baking pan until neck is tender, about 1 hour. Remove from oven and reduce oven temperature to 163°C. Cool squash to warm.

Butter an 8- by 2-inch round cake pan. Line bottom with a round of parchment or wax paper and butter paper.

Scoop flesh from squash, discarding skin, and purée in a food processor until smooth, about 45 seconds. Put 475ml purée in a bowl, then whisk in whole eggs, 120g half-and-half, 2 tablespoons cheese, 1 1/4 teaspoons salt, and 1/2 teaspoons black pepper until combined.

Pour squash mixture into cake pan and bake in a water bath until just set and a wooden pick or skewer comes out almost clean, 45 minutes to 1 hour. Remove from water bath and cool flan in pan on a rack 15 minutes. Invert a flat plate over flan, then invert flan onto plate and carefully remove parchment.

Meanwhile, bring whole sage leaves and remaining cup half-and-half just to a simmer in a 1- to 2-quart heavy saucepan, then remove from heat and let steep, covered, 10 minutes.

Remove sage, carefully squeezing leaves to extract liquid, and discard leaves.

Whisk yolks into half-and-half and cook over moderately low heat, stirring constantly with a wooden spoon, until sauce is thick enough to coat back of spoon and registers 170 to 79°C on thermometer, about 4 minutes (do not let boil).

Immediately pour sauce through a fine-mesh sieve into a bowl, then add remaining 60g cheese and chopped sage, stirring until cheese is melted. Stir in 1/4 teaspoons salt and 1/2 teaspoons pepper.

Cut flan into wedges with a thin knife, wiping knife clean after each slice. Serve flan with sauce.

Disclaimer

While every effort has been made to ensure the information is accurate and up to date, individual needs may vary and dietary requirements can differ based on personal health conditions. Always check food labels and allergen information before preparing or consuming any recipe. If you have specific health concerns, allergies, intolerances, or are following a medically prescribed diet, seek advice from your GP, pharmacist, or a registered dietitian before making significant changes to your diet or lifestyle.

Article history

The information on this page is peer reviewed by qualified clinicians.

  • 17 Jan 2026 | Originally published

    Authored by:

    UK recipe editors

    Peer reviewed by

    UK recipe editors
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