Line a loaf pan with plastic wrap, leaving overhang, and chill it in the freezer.

Toss raspberries with lemon juice and a small portion of sugar, then lightly crush and refrigerate.

Whisk egg yolks with remaining sugar and cook gently over simmering water until thick and pale.

Remove from heat, add vanilla and salt, and whisk briefly to cool.

Whip heavy cream to soft peaks.

Fold whipped cream into the yolk mixture until light and smooth.

Gently fold in crushed raspberries.

Transfer mixture to the prepared pan, smooth the top, and cover.

Freeze for at least 6 hours, then unmold, slice, and serve.