Preparation

Make the biscuit dough

• In the bowl of a food processor, pulse the flour, sugar, baking powder, salt, and lemon zest to combine, 15 to 30 seconds.
• Add the butter and pulse until the mixture resembles coarse meal with pieces no larger than the size of a pea, 1 to 2 minutes more.Transfer to a medium bowl.
• Make a well in the center of the bowl, pour in the cream, and toss well to combine. Gently combine the mixture into a dough, being careful not to overmix.
• Cover the bowl with plastic wrap and refrigerate while you make the filling. (The biscuit topping can be made up to 1 day ahead; keep covered in the refrigerator.)

Make the filling

• In a small bowl, combine the sugar and cornstarch. In a large bowl, toss the blueberries with the sugar mixture. Add the lemon zest, and toss well to combine.

Assemble and bake the cobbler

• Position a rack in the center of the oven and heat to 400°F.
• Butter a shallow 3-quart baking dish (or individual dishes;see tip). Pour the fruit into the prepared dish.
• On a lightly floured work surface, pat the dough into a rectangle about 3/4 inch thick. Cut biscuits using a round cutter dipped in flour, or use a knife to cut into squares. If using a biscuit cutter, save the scraps and rework the dough to cut more rounds. Arrange the biscuits over the fruit about 1 inch apart.
• Brush the egg wash over the tops of the biscuits; you won’t need it all. Sprinkle the almonds evenly over the biscuits.
• Transfer the cobbler to the oven, and bake until the biscuits are evenly golden and the fruit filling is bubbly in the center of the dish, 30 to 35 minutes. Rotate the cobbler halfway through baking time for even browning. If browning too quickly, reduce the oven temperature to 375°F and tent the baking dish with foil. Let the cobbler cool for at least 45 minutes before serving warm.