Preheat oven to 350°F (175°C). Line two baking sheets with parchment paper.
In a bowl, rub together sugar and lemon zest with your fingers until fragrant.
Add butter and brown sugar. Mix on medium-high speed for 3–4 minutes until fluffy.
Add egg yolk, lemon juice, and vanilla. Mix to combine.
Slowly add salt, baking powder, baking soda, and flour. Mix just until combined.
Fold in chopped frozen raspberries gently. Don’t overmix.
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