Bake these delicate jam-filled biscuits at Christmas. They're a Finnish festive tradition, and the secret to their delicious nutty flavour is the brown butter

• Preparation and cooking time
  • Prep:1 hr and 15 mins
  • Cook:12 mins
  • plus cooling
• More effort
• Makes 30 biscuits

• Vegetarian

Ingredients

• 200g unsalted butter
• 125g caster sugar
• 2 tsp vanilla sugar or 1 tsp vanilla paste
• 300g plain flour
• 1 tsp bicarbonate of soda

For the filling

• 75g good-quality or homemade raspberry jam
• 50g caster sugar

Method

• STEP 1

  Heat the oven to 195C/175C fan/gas 51/2 and line two baking sheets with baking parchment.

• STEP 2

  Melt the butter in a saucepan over a low heat and cook for 10 mins, stirring regularly, until it turns golden and smells slightly nutty. Keep an eye on the colour as the butter can burn quickly. Immediately pour the butter into a large bowl, add the sugar and vanilla, and mix thoroughly. Leave to cool a little, then sieve in the flour and bicarb.

• STEP 3

  Use a large teaspoon to scoop pieces of the mixture and mould them, pushing down slightly to flatten the tops and smoothing away the excess on the sides with a finger. Slide off the spoon and arrange on the prepared baking sheet, flat side down. Repeat with the remaining mixture. Bake for 10-12 mins until light golden. Leave to cool completely.

• STEP 4

  Spread a small amount of jam on the flat side of each biscuit. Sandwich with another biscuit. Tip the sugar onto a plate, then roll each of the biscuits in it to coat.