STRAWBERRY-rhubarb cobbler with meyer lemon biscuits

(adapted from Carla Snyder)
makes 4 servings
Lightly butter 4 six-oz. ramekins. Preheat the oven to 400° F.
 
For the filling-
6 oz. fresh or frozen rhubarb (if frozen, lay the rhubarb out on a double thickness of paper towels and blot off excess ice crystals; if fresh, rinse, remove leaves, and dice)
1½ cups fresh strawberries, quartered
½ cup granulated sugar
¼ cup firmly packed brown sugar
zest from 1 Meyer lemon
2 tablespoons cornstarch
pinch of kosher salt
2 teaspoons Meyer lemon juice

In a large bowl, combine the granulated and brown sugars; add the lemon zest, rubbing it in with your fingers until fragrant. Whisk in the cornstarch, salt, and Meyer lemon juice. Add the rhubarb and strawberries; toss to coat until thoroughly combined with the sugar mixture.  Set aside.
 
For the biscuits-
1 cup all-purpose flour
1½ teaspoons baking powder
1½ tablespoons granulated sugar
zest from 1 Meyer lemon
⅛ teaspoon kosher salt
¼ cup cold, unsalted butter, cut into small pieces
⅓ cup buttermilk
2 tablespoons of beaten egg (this is ½ of a large egg, beaten- I refrigerate the leftovers to use as egg wash)
coarse sanding sugar for sprinkling
 
In a large bowl, whisk together the flour, baking powder, sugar, lemon zest, and salt. Add the butter pieces. Toss the butter with the flour mixture then rub the butter pieces into the dry ingredients until no large pieces of butter remain. In a small bowl, whisk together the buttermilk and the 2 tablespoons of beaten egg. Gradually add the buttermilk/egg mixture to the butter/flour mixture, tossing it with a fork just until the dough barely holds together, taking care not to over mix.
 
To assemble-
 
Divide the strawberry/rhubarb mixture evenly between the four ramekins. Dollop spoonfuls of the biscuit dough evenly over the fruit. Sprinkle the tops of the biscuits with coarse sanding sugar. Transfer the ramekins to a parchment lined baking sheet. Bake on the middle rack of the preheated 400° F oven for 25-30 minutes, or until the fruit bubbles around the edges of the ramekins and the biscuits are deeply golden.  Transfer the baking sheet to a cooling rack. Let the cobblers cool slightly before serving. If serving for breakfast, top with dollops of yogurt; for dessert, serve with lightly sweetened whipped cream. Cover and refrigerate any leftovers.
 
(Note: Recipe can be doubled and baked in a 2-qt. baking dish)