Preheat oven to 400º and butter a 9 x 13 casserole dish.
In a large skillet add butter and saute onions over medium heat until soft. Increase the temperature to medium high and add squash, stirring for about 5 minutes. Add corn, chicken stock, lemon juice, salt and pepper. Reduce heat to medium and cook for 5 minutes stirring frequently. Let cool to room temperature.
Mix parmesan and flour together in a small bowl and add to cooled squash mixture. Empty into casserole dish.
BISCUITS
Add finely shredded cheese, chives, flour, baking powder and salt to a food processor and pulse until combined. Add cold butter and pulse until the mixture resembles peas. Drizzle buttermilk while continuing to pulse just until it comes together. Use a large ice cream scoop to scoop dough onto top of casserole.
Bake at 400º for 15 minutes and then reduce to 350º and continue baking for 20-30 minutes until the squash is soft. Cover the top of cobbler with foil if biscuits begin to brown too much.
Barbara's Notes + Tips
Cover the biscuits with foil if they start to brown and are not cooked through.
You can make this ahead of time, just let it come to room temperature before baking.
For more buttery biscuits, brush melted butter over the top after removing from the oven.
You can substitute vegetable broth for chicken broth to make this vegetarian.