Preheat your oven to 375°F. Line every other cup in a 12-count muffin tin.

In a saucepan over medium-high heat, combine raspberries, sugar, and lemon juice. If using fresh berries, add the water. Bring to a boil, then reduce heat to low. Use a fork or masher to break down the berries. Sift in the flour and stir well. Let simmer for about 5–6 minutes, or until thickened. Remove from heat and let it cool.

In a bowl, combine flour, sugar, salt, cardamom, and melted butter for the streusel topping. Mix until crumbly and set aside.

In a large bowl, stir together flour, baking powder, salt, and cardamom. In a separate bowl, whisk the eggs, buttermilk, sugar, vanilla extract, olive oil, and melted butter until fully blended. Gently fold the dry ingredients into the wet ingredients just until combined—do not overmix.

Fold in the raspberries and white chocolate chips carefully to avoid breaking up the berries too much.

Use a scoop or large spoon to fill the muffin liners evenly. Add about a tablespoon of raspberry swirl on top of each muffin. Then sprinkle generously with the streusel topping.

Bake at 375°F for 5 minutes. Then reduce the oven temperature to 350°F and continue baking for another 15–20 minutes, or until a toothpick inserted in the center comes out clean.

Allow muffins to cool in the pan for at least 10 minutes before removing. Serve warm or at room temperature.