Cook the macaroni to al dente. Drain the pasta and set aside.
In a large heated skillet, melt the butter and add in the flour, whisking until it's nice and smooth.
Pour in the milk and continue whisking and then let the milk mixture simmer for a few minutes until the mixture thickens up.
Reduce the heat and then add the salt, shredded mozzarella and jalapeño cheddar cheese. You can add little pieces of chopped jalapeño at this point.
When the cheese completely melts out, add the cooked pasta and stir to coat well.
Add more sliced jalapeño and jalapeno cheddar cheese on the top. Spread the toasted panko breadcrumbs evenly to cover the cheese. I usually toast the breadcrumbs in a skillet, giving them a light spray of olive oil to obtain a nice golden color.
Place in the oven and bake for 10 minutes on 400 degrees F. Remove and let cool for a few minute then serve.