Preheat the oven to 350°F, and line cupcake pan with cupcake liners.

Cream together butter and sugar until light and pale in a large bowl with an electric mixer. About 2 minutes.

Add the eggs, lemon zest and juice, vanilla, salt, flour and baking powder. Mix at medium speed for 2 minutes, until well combined. Then fold in the raspberries.

Bake for 19-24 minutes, until golden. Transfer to a wire cooling rack to cool.

For the buttercream, put the raspberries and lemon juice in a small saucepan over low heat. Heat them slowly until they begin to break down, then mash them with a fork, and simmer for 10 minutes. Press the cooked raspberries through a sieve to get the juice, and allow to cool.

Beat the softened butter in a mixer for 5 minutes, until pale. Add the confectioners’ sugar in 2 stages, mixing for 2 minutes each time. When fully mixed, gradually add the raspberry juice and mix until the butter cream is pink, and fluffy in consistency.