Preheat your oven to 325°F (160°C).
Get your bundt cake pan ready by greasing it really well! First, coat it thoroughly with a solid fat like butter or coconut oil. Then, use a cooking spray (like coconut or avocado oil) and finally, dust it lightly with a few tablespoons of almond flour. This triple-greasing helps prevent sticking.
In a medium bowl, whisk together the almond flour, coconut flour, whey protein powder, baking powder, and salt until they are fully combined.
In a large mixing bowl, beat the softened butter and granular sweetener together until the mixture is light and wonderfully creamy.
One by one, beat in the room temperature eggs, ensuring each is fully incorporated before adding the next. Stir in the vanilla extract.
Gradually add the dry flour mixture to the wet ingredients, mixing on low speed until just combined.
Finally, gently beat in the whipping cream and water until the batter is smooth.
Pour the batter into your perfectly prepared bundt pan and smooth the top evenly.
Bake for 50 to 60 minutes, or until the cake is golden brown on top and feels firm to the touch.
While the cake is still warm and resting in the pan, prepare the glaze. In a small saucepan over low heat, melt the butter and granular sweetener together, whisking until smooth and fully combined.
Remove from heat and whisk in the water and vanilla extract.
Using a skewer, poke holes all over the warm cake in the pan. Make sure to get plenty of holes for the glaze to soak into!
Slowly pour the warm butter glaze evenly over the poked cake, allowing it to seep into all the holes.
Let the cake cool completely in the pan. This step is crucial for the cake to set properly and prevent sticking.
Once fully cooled, carefully loosen the sides of the cake from the pan using a thin knife or rubber spatula.
Invert the cake gently onto a serving platter.
Dust the top with powdered sweetener for an elegant finish.
Serve slices with a dollop of lightly sweetened whipped cream and fresh berries for an extra healthy touch, if desired!