Preheat oven to 375°F / 190°C. Line a ベーキングトレイ with parchment paper.

Measure the flour, baking powder, and salt, and sift them together into a small bowl.

In another small bowl, lightly whisk the egg. Then mix in the raspberry jam, pure vanilla extract, and red food colouring.

Using a スタンドミキサー or a wooden spoon, whip the butter and sugar together until they are fluffy and lighten in colour. I used a stand mixer on medium-high for 4 minutes. Whipping these together properly is crucial for achieving the fluffy, cake-like texture of these cookies.

Stir your raspberry jam mixture into the whipped butter and sugar; mix together well. The texture will look a bit grainy.

Add in the dry ingredients and mix until just completely incorporated (do not overmix!).

Gently fold the raspberry and white chocolate pieces into the cookie dough.

Use a tablespoon-sized measuring spoon to scoop the cookie dough onto the parchment paper-lined baking sheet. The spoonful should be rounded (see image in post above for reference). You should end up with twelve cookies in total. The cookies will spread slightly, so ensure that there is some space between them.

Bake in preheated oven about ten minutes. You will notice a very light browning at the edge of the cookies when they are done. Do not to over-bake them.

The cookies will be extremely delicate when you pull them from the oven. Allow them to cool on the baking sheet for five minutes before transferring to a cooling rack to cool the rest of the way.