Sunday Supper: Blueberries

I have a theory that blueberries are the most quietly satisfying fruit of the whole summer. Peaches get the romance. Strawberries get the attention in spring. Watermelon gets the whole back porch and a pile of paper towels. Blueberries just sit there in their pint container, deep blue and unbothered. Then you eat a handful and remember why you’ve been buying them every July for as long as you can remember.

They don’t demand much from the cook, which is a virtue in late July, when the kitchen is already warm, and the garden is asking enough of everybody. Eat them plain, put them in a muffin, drop them into a bowl of yogurt, or bake them into a coffee cake that makes the whole house smell like a Sunday morning should. All of those are correct answers.

This week, the Larder is sharing a coffee cake recipe because it is the version of blueberries that belongs most squarely on a Sunday supper table. And a good coffee cake is one of the more underrated things a kitchen can produce on a summer weekend.

Choosing the Blueberries

Look for berries that are deep blue all the way around, firm to the touch, and covered with a silvery-white bloom. That bloom, called a wax bloom, is a natural coating the berry produces and a reliable sign of freshness. Berries that have lost their bloom or turned soft are past their moment. Those showing red or green at the stem end may not yet be fully ripe.

Bigger isn’t always better with blueberries. Smaller, wild-style berries tend to have more concentrated flavor than the large cultivated varieties, though the large ones work perfectly well in baking, where the berries will break down in the oven anyway. For eating out of hand, find the smallest, darkest ones you can.

Don’t wash blueberries until you’re ready to use them. Washing removes the bloom and speeds up softening. Rinse them just before they go into the batter or onto the table—not the day before.

If you missed the adventure of picking your own at Baird Mountain Blueberry Farm right here in Moore County, be sure to put a stop on your plans for next year. My husband and I spent an early morning filling buckets a few weeks ago during the peak of the harvest. I was able to stock my freezer with plenty to get us through until next season!

Blueberry Coffee Cake

This is the kind of cake that works as a Sunday morning breakfast, a Sunday afternoon dessert, or something set out on the counter to feed whoever wanders through the kitchen. It is not a complicated cake, but each bite has a flavor that feels like home.

For the cake:
• 2 cups all-purpose flour
• 2 teaspoons baking powder
• 1/2 teaspoon salt
• 3/4 cup sugar
• 1/2 cup butter, softened
• 2 large eggs
• 1 teaspoon vanilla extract
• 1/2 cup sour cream
• 1/4 cup whole milk
• 2 cups fresh blueberries

For the streusel topping:
• 1/2 cup all-purpose flour
• 1/2 cup sugar
• 1 teaspoon cinnamon
• 4 tablespoons cold butter, cut into small pieces

Making the Streusel

Start with the streusel so it can go into the refrigerator while you make the batter. Cold streusel holds its texture better in the oven than streusel made with warm butter. The difference shows up in the finished cake as a crumblier, more distinct topping rather than one that melts into the surface.

Combine the flour, sugar, and cinnamon in a bowl. Add the cold butter pieces and work them in with your fingers, pressing and rubbing until the mixture holds together in pea-sized clumps when you squeeze a handful. It should look shaggy and uneven, not smooth. Refrigerate until the batter is ready.

Making the Batter

Preheat the oven to 350 degrees. Grease a 9-by-13-inch baking pan or a 9-inch square pan for a thicker cake.

Whisk the flour, baking powder, and salt together in one bowl and set aside. In a larger bowl, beat the softened butter and sugar together until pale and fluffy, about three minutes with a hand mixer. Add the eggs one at a time, beating after each addition, then add the vanilla. Mix in the sour cream and milk until just combined. The batter may look slightly curdled at this stage; that’s fine.

Add the flour mixture and fold it in gently until just combined. Do not overmix. A few streaks of flour remaining in the batter are better than a tough cake caused by overstirring.

Toss the blueberries with a tablespoon of flour before folding them into the batter. This step is worth doing: The flour coating helps the berries stay suspended in the batter rather than sinking to the bottom during baking. Fold them in with a spatula, using the gentlest hand possible, because overworked blueberries will streak the batter purple and break apart before they ever reach the oven.

Baking

Spread the batter evenly in the prepared pan. Pull the streusel from the refrigerator and scatter it over the batter in an even layer, pressing it down very lightly so it adheres without packing.

Bake for 40 to 45 minutes in a 9-by-13-inch pan or 45 to 50 minutes in a 9-inch square pan, until a toothpick inserted in the center comes out clean and the streusel is golden brown. The center of the cake should feel set, not jiggly, when you give the pan a gentle shake.

Let the cake cool in the pan for at least 15 minutes before cutting. The blueberries hold a tremendous amount of heat and will burn anyone who tries to eat a slice straight out of the oven – knowledge hard-won and not forgotten.

Blueberries Beyond the Cake

A coffee cake is not the only thing blueberries do well in a summer kitchen. A handful stirred into pancake batter on a slow Sunday morning is one of the simpler pleasures of the season. Blueberries cooked down briefly with a little sugar and lemon juice become a quick sauce that belongs on biscuits, ice cream, or a bowl of oatmeal.

Frozen blueberries are worth putting up when the fresh ones are at their best and least expensive. Spread them in a single layer on a sheet pan, freeze until solid, and then transfer them to a freezer bag. They’ll keep for months and can go straight from the freezer into muffin batter or a smoothie without being thawed first – which is one of the more useful things a late-summer kitchen can produce for the months ahead.