Imagine starting your day with a slice of warm, fragrant cinnamon coffee cake. This recipe offers a delightful twist on the traditional breakfast treat, delivering a moist and tender cake with a swirl of cinnamon spice nestled within. The top is crowned with a generous layer of buttery crumbs, providing a satisfying crunch that perfectly complements the soft interior.

Crafted with almond flour, this cake offers a naturally gluten-free option for those with dietary considerations. The addition of sour cream to the batter ensures a remarkably moist crumb, preventing any dryness and creating a melt-in-your-mouth texture. Be sure to use sour cream at room temperature to ensure it blends smoothly into the batter, creating a velvety consistency.

The nutty notes of walnuts pair exquisitely with the warmth of cinnamon, but feel free to experiment with other nuts to your liking. Pecans offer a similarly rich and buttery flavor, while slivered almonds or chopped hazelnuts can provide a more delicate crunch. Be mindful that certain nuts, like peanuts, may not complement the cinnamon as harmoniously.

This cake is best enjoyed fresh, its aroma filling your kitchen and its flavors dancing on your palate. It's the perfect accompaniment to a steaming cup of coffee or tea, making for a truly satisfying morning or afternoon indulgence. While it's unlikely to last long, any leftover cake can be stored in an airtight container at room temperature for a few days.

For longer storage, wrap individual slices tightly and freeze them for up to a month, thawing as needed for a convenient and delicious treat. For those following a vegan lifestyle, this recipe can be easily adapted with a few simple substitutions. Dairy-free sour cream can replace the traditional sour cream, while vegan butter or coconut oil can be used in place of butter.

Chia seeds or ground flax seeds, when mixed with water, serve as an excellent egg replacement, binding the ingredients together and maintaining the cake's moist and tender texture.