Michigan Blueberry Crumble Bars

Michigan is one of the top blueberry-producing states in the country, and July is when local blueberries really hit their stride. These crumble bars are the perfect way to use them — the same buttery oat mixture forms both the base and the crumble top, sandwiching a thick layer of fresh berries. They’re easy to make, cut cleanly, travel perfectly to a cookout, and are genuinely hard to stop eating.

Ingredients

For the oat crumble (base + topping):

• 2 cups all-purpose flour
• 1½ cups old-fashioned rolled oats
• ¾ cup granulated sugar
• ¼ cup packed brown sugar
• ½ teaspoon cinnamon
• ½ teaspoon kosher salt
• ¾ cup (1½ sticks) unsalted butter, melted

For the blueberry filling:

• 3 cups fresh Michigan blueberries (about 1½ pints)
• 3 tablespoons sugar
• 1½ tablespoons cornstarch
• 1 tablespoon lemon juice
• ½ teaspoon lemon zest
• Pinch of cinnamon

Instructions

1. Preheat and prep. Heat oven to 350°F. Line an 8x8 or 9x9 inch baking pan with parchment paper, leaving some overhang on the sides so you can lift the bars out cleanly.

2. Make the crumble. In a large bowl, stir together flour, oats, granulated sugar, brown sugar, cinnamon, and salt. Pour in melted butter and stir until everything is evenly moistened and clumping together. It should hold when you squeeze it.

3. Press the base. Spread about two-thirds of the crumble mixture into the bottom of the prepared pan. Press it down firmly into an even layer — use the flat bottom of a measuring cup to pack it tight. Set remaining crumble aside.

4. Make the blueberry filling. In a medium bowl, gently toss blueberries with sugar, cornstarch, lemon juice, lemon zest, and a pinch of cinnamon until evenly coated.

5. Assemble. Spread the blueberry mixture evenly over the crumble base. Scatter the remaining crumble mixture over the top in small clumps — don’t press it down, just let it sit loosely so it bakes up crunchy.

6. Bake. Bake 38–42 minutes until the topping is golden brown and the blueberry filling is bubbling at the edges. The bubbling is important — it means the cornstarch has cooked through and the filling will set properly.

7. Cool completely before cutting. This is the hardest part. Let the bars cool in the pan for at least 1 hour, then refrigerate for another 30 minutes before lifting out and slicing. If you cut them warm, they’ll fall apart.

8. Slice and serve. Lift the parchment out, set on a cutting board, and cut into 16 bars. Store in the refrigerator for up to 4 days.

Tips

• Fresh blueberries only. Frozen berries release too much liquid and make the filling watery. July is peak local blueberry season in Michigan — this is the recipe to make when you have fresh ones.
• Don’t skip the parchment. You need the overhang to lift the bars out cleanly. Greasing the pan alone won’t work.
• They travel beautifully. Stack them between layers of parchment in a container. No fork needed, no risk of melting — perfect for the 4th of July.
• Make them the night before. These actually taste better the next day after the filling has had time to fully set. Make them July 3rd and bring them to your cookout on the 4th.

Where to Find Local Blueberries

Michigan blueberries are just arriving at Washtenaw County farmers markets in early July. Look for them at the Ann Arbor Farmers Market, Ypsilanti Farmers Market, and Saline Farmers Market on Saturday mornings — ask vendors when you arrive, they’ll tell you exactly what they have.

For u-pick and farm-direct blueberries, you have three great local options:

• Dexter Blueberry Farm — 11024 Beach Rd, Dexter. U-pick blueberries starting in July, running approximately 6 weeks. Call ahead for current conditions before visiting.
• Blueville Acres Blueberry Farm — 38093 Judd Rd, Belleville. U-pick blueberries mid-July through mid-August.
• Kapnick Orchards — 4245 N Rogers Hwy, Britton. Farm market open year-round with blueberries when in season.

Once local blueberries are in, they’re everywhere through August — and this is the recipe to make when you have them fresh.