Bring a large pot of water to boil over high heat. Add the prepared beans to the boiling water, cooking for 5 minutes.
After 5 minutes, immediately drain the beans and then transfer them to a bowl of ice water. Set aside.
Set a large skillet over medium heat. Add the garlic and let it cook for 30-60 seconds, just to cook off any bitter taste.
Add the remaining ingredients (EXCEPT THE BEANS, PESTO, AND CHEESE) to the skillet. Whisk them together until evenly combined. Bring the sauce to a nice simmer, then reduce the heat slightly. Let the sauce simmer, stirring often, for 5 minutes- just until thickened some.
Remove the skillet from heat and stir in 1/2 cup of the Parmesan cheese & the pesto until completely incorporated.
Add the beans to the skillet, tossing gently to incorporate.
Spray a 9x13" baking dish with nonstick cooking spray. Add the beans to the dish, and spread out evenly. Sprinkle the remaining 1/4 cup of cheese evenly out overtop, followed by the fried onions.
Bake at 400°F for 15 minutes.
Serve warm & enjoy!