An old-fashioned dessert with a twist, this raspberry and white chocolate loaf cake is springy, tender, and loaded with fruit and chocolate! Add extra white chocolate chips to the top to experience the incredible deliciousness of caramelized white chocolate.
Preheat the oven to 350°F (180ºC). Lightly spray a 9x5-inch (23x13-cm) standard loaf tin with baking spray and line it with parchment paper. Set aside.
Use a hand or stand mixer to mix the butter and sugar together on medium-high speed until well combined, about 1 to 2 minutes.
Add the eggs one at a time, mixing well between each addition.
Add the sour cream and vanilla and mix.
Switch to a spatula or wooden spoon. Sift the flour into the bowl then sprinkle the baking powder, baking soda, and salt evenly over the top. Gently fold the dry ingredients in about halfway.
Add the frozen raspberries and white chocolate chips. Continue to gently fold until the raspberries and chocolate are well distributed and the flour is just mixed in.
Spoon the batter into the prepared tin and smooth the top. Sprinkle a few extra raspberries and white chocolate chips on top if you like, then cover the tin loosely with foil. Bake the loaf for 40 minutes, then remove the foil and bake for another 25 to 30 minutes, or until the top of the loaf springs back when lightly pressed with a fingertip and the cake is starting to pull away from the sides of the tin. Transfer the tin to a wire rack and cool for 10 minutes. Lift the loaf out of the tin and onto the wire rack to cool completely before icing or slicing.
Notes
It's important to cover the tin loosely with foil before baking so the outside of the loaf doesn't overbake before it's cooked through the middle.
The top of the cake may look overdone after baking, however, much of the golden color actually comes from the white chocolate caramelizing in the oven.
The cake itself is dense and will be flat on top, probably level with the top of the tin.
You may see a tinge of blue streaking through your loaf's inside crumb. This is a natural reaction between the raspberries and baking soda and is nothing to worry about.
Store the white chocolate raspberry loaf cake at room temperature for up to 3 days, wrapped in plastic wrap, or in an airtight container. You can also store the cake in the refrigerator for up to 5 days.
If you want to freeze the whole cake, wrap it in plastic wrap and aluminum foil—this will help prevent freezer burn. The loaf can be stored in the freezer for up to 2 months. You can also freeze individual slices. Slice the cake then place them in a freezer-safe container or zip-top bag. Store the slices in the freezer for up to 1 month. When you're ready to eat the cake, let it thaw at room temperature for about 1 hour, or in the refrigerator overnight.