In a large skillet over medium heat, add butter and oil.
When it starts to sizzle, add onions, season lightly with salt and sauté for 1 minute. Add red peppers and sauté for 1 minute.
Add mushrooms and combine with the other ingredients; season with black pepper. Mix to coat, place the lid on and simmer for 2 minutes.
Remove the lid, stir the veggies and leave it like this for 45 to 60 seconds so the liquid can mostly evaporate.
Add pressed garlic and quickly sauté it for 1 minute.
Pour in heavy cream and chicken broth. Add cheese, Herbes de Provence and hot paprika. Blend the ingredients and bring the mixture to a simmer.
Preheat oven to 350ºF
Stir in almonds before pouring in the cornstarch mixture; stir until the sauce thickens, about 45 seconds.
Add blanched green beans and stir to coat.
Removing from the heat and transfer the mixture into a 3-quart baking dish that has been greased with cooking spray; spread it out evenly.
Combine breadcrumbs and melted butter together. Spoon on the topping evenly on top and sprinkle on mild paprika.
Transfer the dish to the preheated oven and bake until hot and bubbly, about 20 minutes.