Twice Baked Spaghetti Squash and Cheese

INGREDIENTS

medium spaghetti squash, halved lengthwise and seeds removed

5 tbsp

butter, divided

1/2 cup

onion, finely chopped

2 tbsp

all-purpose flour

1 tsp

mustard powder

2 cups

milk (can use skim, 1%, 2% or whole)

8 oz

sharp cheddar cheese, shredded

1 tsp

salt

1/4 tsp

ground pepper

1 cup

panko bread crumbs