Note: I made this in a shallow tart pan, but you could easily use a normal pie dish.
Growing up, dessert meant lots of white sugar, white flour, and usually lots of icing. Pound cake, lemon meringue pie, and Texas sheet cake were standards at the Sunday table. And I did eat of the fruit of the tree, and I did eat well, which is probably why I love more complex flavors now. There's nothing wrong with sugar cookies frosted with tongue-wrinklingly sweet pink icing, but you appreciate those finer things when the times you eat them are few and far between. Having said that, I am a baker at heart. Roasting meat intimidates me a little, but give me a sourdough starter or a good scone recipe and I feel right at home. I thrive amid flying flour and whipped egg whites. When I used to work at the bakery my hair smelled of flour, and I loved that my hair smelled of flour.
But even bakers can get the red velvet blues. I often do. Which is why I keep an arsenal of whole grain recipes in my repertoire. They tend to be a little more savory, and more wholesome. This Sweet Potato Coffee Cake was dreamed up after making sweet potato latkes and having quite a bit of grated sweet potato left over. I imagine that grated winter squash, carrots, or zucchini would be equally fitting in this recipe.
A note about spelt flour: for baked goods, spelt is the perfect whole grain substitute because this flour is not conducive to developing gluten. Gluten is a protein composite that causes bread to be chewy and is something that you don't want to encourage in most baked goods. When cake recipes tell you not to overmix the batter, it is because you might develop the gluten too much, resulting in a tough end product. This is why you might choose to use cake flour for making a cake and bread flour for making bread. Cake flour has a low protein content, and bread flour has a much higher protein content. You need lots of protein in your flour when baking bread so that the dough is strong enough to capture gas bubbles created by yeast, allowing your bread to rise higher. Using spelt flour makes for more tender baked goods and can easily be substituted for all-purpose flour or whole wheat flour. The only consideration you may need to make when substituting spelt flour is that spelt can absorb more water. If your batter feels too dry when making substitutions with spelt, simply add a little more liquid until you have reached the desired consistency.
I have included a lot of optional ingredients in this recipe. I am not in any way suggesting that you use all of them at once. Simply use what you have on hand or substitute other ingredients that you like. Coffee cake is one of those recipes that will usually do your bidding.
Preheat the oven to 350°. Rub a 9-inch springform pan or muffin tins with a 1/3-cup capacity with butter or spray with baking spray.
For the streusel topping, measure into a mixing bowl:
¼ cup plus 2 tablespoons whole wheat spelt flour
2 tablespoons wheat germ or oat bran
2 tablespoons dark brown sugar
1 tablespoon sugar
1/8 teaspoon salt
Combine thoroughly and add:
3 tablespoons safflower oil
Mix in with your fingers until the mixture is pebbly-looking and the oil is incorporated. Set aside.
Measure into a separate large bowl:
1 cup whole wheat spelt flour
¾ cup all purpose flour
¼ cup wheat germ or oat bran
1/3 cup dark brown sugar
¼ cup sugar
½ teaspoon cardamom
¼ teaspoon nutmeg
½ teaspoon cinnamon
1 teaspoon salt
1 teaspoon baking powder
½ teaspoon baking soda
(½ cup toasted coconut)
(½ cup golden raisins or chopped dried apricots)
(1/3 cup finely chopped candied ginger)
Mix thoroughly. Stir in:
1 ½ cups coarsely grated sweet potato
¼ cup safflower oil
1 cup buttermilk
(1 teaspoon orange zest)
Mix just until the wet ingredients are combined. Scrape the batter into the prepared pan or muffin tin. If using muffin tin, the batter should be slightly mounded above the edge. Sprinkle the streusel topping evenly over the coffee cake or muffins.
Bake for 32 to 35 minutes for muffins, 42 minutes for the coffee cake, or until a toothpick or wooden skewer inserted into the center of the coffee cake or muffins comes out with moist crumbs on it. Remove from the oven. To ensure that the muffins stay crusty, twist each muffin out and place it on its side in the cup to cool. For the coffee cake, immediately remove the ring of the springform pan. Serve immediately or keep in an airtight container for up to two days. These can also be frozen and reheated.