Think of this tart as the French version of the popular pecan pie, but with distinct bitter-sweet balance, and a botanical note. Walnut tart is a specialty from the French Alps where I grew up, famed for its delicious walnuts. I have fond memories of picking a glossy sticky walnut tartelette as a treat when I was younger. This version with a rosemary flavored caramel is my take on it, which brings a delicate herbal flavour to the buttery caramel.
250g Plain Flour
125g Caster Sugar
125g Unsalted Butter, in small cubes
1 Whole Egg and 1 Egg Yolk
230g Walnut Halves
75g Light Soft Brown Sugar
4 Tbsp Milk
200g Double Cream
1 Sprig of Rosemary, finely chopped
THE SWEET PASTRY CRUST
1. In a food processor with the blade attachment add the flour and sugar. Mix them up a little and add the cold butter. Blitz for a few seconds (or using your fingertips) until the mixture resembles the texture of sand.
2. In a small bowl, beat the egg and egg yolk with a teaspoon of cold water and add to the flour and sugar until the egg is incorporated and the mixture starts to come together. It is perfectly fine if your mixture is a little crumbly, the key here is to work fairly fast and avoid overworking the pastry. Roughly create a flat round shape, wrap it in cling film, and place in the fridge for 30 minutes.
3. Preheat the oven to 180Cº.
4. Generously butter the inside of a 25cm tart tin. Roll out the chilled pastry and place it in the tin. If there are any cracks, just bind the pastry back together with your fingers. Cut out the excess pastry and press the sides so that the pastry overhangs by a few millimetres, as it will shrink back down when baking. Lastly, prick the base with a fork, cover with shrunken up greaseproof paper and fill to the brim with baking beans, or rice.
5. Place in the freezer for 15 minutes, then take it out and bake it in the oven for 25 minutes. Once it is very slightly coloured, take off the paper and beans and place it back in the oven for 5 minutes.
THE ROSEMARY CARAMEL
1. In a wide frying pan, add the milk, the light soft brown sugar, and honey. Heat up on very low heat for 5 minutes, stirring continuously.
2. Add the double cream and the small sprig of rosemary, chopped up finely. Cook for a further 15 minutes, until the mixture, is glossy and coats your spoon.
3. Add the nuts and cook for 5 minutes on medium heat, stirring with a spoon. Take off the heat, add the butter, and once well incorporated pour into the tart case.
4. Leave to cool and place in a cold area for 30 minutes before serving.