Dice jalapeno, onion, red bell pepper, and celery. Set aside.
Mince garlic and set aside.
Once turkey has been roasted and cooled enough to handle, dice and set aside.
Heat skillet over medium heat and add 1 teaspoon olive oil. Sauté onion, celery, bell pepper, and jalapeno until tender, about 10 minutes.
Add garlic and sauté for 1 minute.
Reduce heat to low and add butter.
Slowly add flour, whisking continuously.
Slowly add milk and whisk continuously until there are no chunks.
Reduce heat to low and add ½ cup shredded cheese.
Let cheese melt then add another ½ cup cheese plus ½ cup of water.
Let cheese melt then add remainder cheese and the remainder of water stirring constantly until cheese is melted and sauce begins to form.
To the skillet, add potatoes and diced turkey. Mix well until combined.
Spread mixture into casserole dish and sprinkle with bread crumbs and paprika.
Bake in the oven for 20 minutes.
Garnish with sliced green onion.