Castagnaccio is a Tuscan cake made with chestnut flour, water, extra virgin olive oil, pine nuts, raisins and rosemary. It contains no sugar, eggs or raising agent: the sweetness comes from the chestnut flour, and the cake is low, dense and moist, with a surface that cracks as it bakes.
In this article you’ll find the recipe for Tuscan castagnaccio for a 26 cm tin, with precise quantities, the right consistency for the batter, baking times, how to choose chestnut flour and the most common variations.
Recipe card
| Item | Details |
|---|---|
| Prep time | 15 minutes |
| Cooking time | 40 minutes |
| Resting time | 15 minutes (soaking the raisins, during preparation) |
| Total time | 1 hour 10 minutes |
| Difficulty | Easy |
| Servings | 8 slices (26 cm round tin) |
| Course | Dessert |
| Cuisine | Tuscan |
| Cooking method | Oven, conventional (no fan) |
Ingredients for a 26 cm tin
- 300 g chestnut flour
- 450 ml cold water
- 40 g pine nuts
- 40 g raisins
- 1 sprig fresh rosemary
- 45 ml extra virgin olive oil (3 tablespoons), plus a little to grease the tin
- 1 pinch of salt (about 2 g)
- 30 g walnut kernels, optional
Chestnut flour. It is the ingredient that determines the flavour. It should be fresh, light hazelnut in colour and sweet-smelling: over time it turns slightly bitter. Flour from the new harvest usually arrives between late autumn and winter. In Tuscany, Farina di Neccio della Garfagnana PDO and Farina di Castagne della Lunigiana PDO are protected.
How to make Tuscan castagnaccio
- Soak the raisins. Place them in a bowl of warm water for 15 minutes, then drain and squeeze them gently.
- Heat the oven. Preheat a conventional oven to 180 °C (350 °F) and grease a 26 cm round tin with a little oil.
- Sift the flour. Sift the chestnut flour into a large bowl together with the salt. Chestnut flour tends to form lumps: this step is essential.
- Make the batter. Pour in the water in a thin stream, whisking, until you have a smooth, lump-free batter. The right consistency is similar to a thick cream: it should fall from the whisk in a continuous ribbon. Add 2 tablespoons of oil and half the pine nuts and raisins.
- Pour into the tin. Pour the batter into the tin: it should be about 1-1.5 cm deep. Scatter the remaining pine nuts and raisins over the surface, the walnuts if using, and the rosemary needles. Finish with the last tablespoon of oil, drizzled over the top.
- Bake. Bake in the middle of the oven for 35-40 minutes. Castagnaccio is ready when the surface is dry, dark and cracked, and the edges come away from the tin.
- Let it cool. Leave it to cool in the tin for at least 15 minutes before cutting: when hot it is very soft and breaks easily.
History and tradition of castagnaccio
Castagnaccio is a cake from the rural cooking of the Apennines, where for centuries chestnuts and their flour were a staple food, so much so that the chestnut tree was called the “bread tree”. It is made throughout Tuscany and in other regions of central and northern Italy, with different names and thicknesses from area to area.
One of the earliest written records is found in the Commentario by Ortensio Lando, published in 1553, which credits the invention of castagnaccio to a certain Pilade da Lucca. Nothing else is known about this figure, and the tradition of the cake is very likely older and more widespread.
After the Second World War, as living conditions improved, castagnaccio lost its role as an everyday sweet in mountain areas and became a seasonal cake, made and sold mainly in autumn.
Practical tips
- Taste the flour before using it. If it is bitter or smells stale, the castagnaccio will too. Keep it in the fridge, tightly closed, and use it within a few months of purchase.
- Adjust the water to the flour. Flours absorb differently: add the water gradually and stop when the batter forms a ribbon. A batter that is too runny gives a rubbery castagnaccio.
- Don’t go above 1.5 cm in height. A castagnaccio that is too thick stays raw in the middle. If you use a smaller tin, increase the baking time by 5-10 minutes and check with a skewer.
- Use a conventional oven. A fan oven dries the surface too much before the inside is cooked.
- Go easy on the rosemary. The needles from one sprig are enough: in larger amounts it masks the chestnut flavour.
Variations and storage
Variations
The base recipe is always the same, but the additions change from area to area. The most common are walnuts, grated orange zest and fennel seeds. Some versions leave out the rosemary. In Livorno a thicker version, about 3 cm high, called toppone, is also made.
Some modern recipes add sugar, cocoa or chocolate chips to suit a sweeter taste. These are legitimate variations, but they move away from the traditional recipe, which uses no sweeteners.
Storage
Castagnaccio keeps at room temperature, covered with cling film or under a cake dome, for 2-3 days. In the fridge it lasts up to 4-5 days, but becomes denser: it’s best to leave it at room temperature for 30 minutes before serving. It can be frozen in slices, but this slightly alters the texture.
Frequently asked questions about castagnaccio
Should castagnaccio be sweetened?
Not in the traditional recipe. Chestnut flour is naturally sweet, and the raisins and pine nuts complete the flavour. If your flour isn’t very sweet or you prefer a stronger taste, you can add 30-40 g of sugar to the batter, but the result moves away from the original Tuscan castagnaccio.
Why is my castagnaccio bitter?
It is almost always down to the flour, either old or badly stored. Chestnut flour goes rancid more easily than cereal flours, especially if kept somewhere warm. Buy flour from the new harvest, check the production date and store it in the fridge in a closed container.
How do I get a soft castagnaccio?
Softness depends on three factors: a batter that isn’t too thick, a depth of at least 1 cm and not overbaking. Take it out of the oven when the surface is cracked but the inside is still moist: it will settle as it cools. Covering it with a tea towel while it cools helps keep it moist.
Is castagnaccio gluten-free?
The ingredients in the recipe are naturally gluten-free. However, anyone who must avoid gluten for health reasons should check that the chestnut flour is certified gluten-free: it may be milled in facilities that also process cereal flours and contain traces.
More traditional Tuscan desserts
Castagnaccio belongs to the family of simple, seasonal Tuscan sweets, together with Siena’s ricciarelli and cantucci, which are made especially during the holiday season. If you’d like to discover more autumn recipes, our collection of traditional Tuscan recipes is a good place to start.
