Bubbly Berry Lattice Pie

The oven bag trick is what makes this blueberry pie different from every other one you’ve baked. Sliding the assembled pie into a large cooking bag before it goes in the oven traps steam around the crust, preventing the edges from burning while the filling bubbles away for a full hour. The result is an evenly browned lattice top and a filling that’s actually thick and set rather than runny.

The filling itself is beautifully simple. A quart of fresh blueberries coated in flour, sweetened with sugar, brightened with a squeeze of lemon juice, and dotted with butter. No cornstarch, no tapioca. Just flour doing the thickening work as the berry juices cook down inside that steamy bag.

Sprinkling sugar and flour on the bottom crust before adding the berries creates a barrier that absorbs the first rush of juice. This prevents the dreaded soggy bottom that plagues most fruit pies.

Pro Tips

• Use a large oven bag (14×20 inches) so the pie fits comfortably without the bag touching the lattice. If the bag rests against the crust, it sticks.
• Cut 6 slits in the top of the bag as directed. Without vents, too much steam builds up and the crust steams instead of baking crisp.
• Bake until the syrup actually boils. You should see bubbling through the lattice openings. If it’s not bubbling, the flour hasn’t activated and the filling will be runny when cool.
• Let the pie cool completely before slicing. Cutting a hot fruit pie gives you blueberry soup. The filling needs at least 2 hours to set.

Variations

• Mixed berry lattice: Replace half the blueberries with fresh blackberries or raspberries for a more complex berry flavor.
• Streusel top: Skip the lattice and top with a brown sugar, butter, and oat crumble instead.