-
1
Butter a shallow 2-quart baking dish; set aside.
-
2
Heat oven to 400u00b0.
-
3
Cook pasta according to package directions; drain and rinse under cold water.
-
4
Transfer to a large bowl and set aside.
-
5
Cook broccoli in lightly salted boiling water 5 minutes, until crisp-tender.
-
6
Drain and rinse under cold water.
-
7
Mix in with noodles.
-
8
Add tuna and toss gently.
-
9
Melt butter in a medium saucepan over medium heat.
-
10
Add onion and cook, stirring occasionally, until soft, about 7 minutes.
-
11
Stir in the cream, water, thickener, salt and pepper; cook until mixture boils and thickens, 5 to 8 minutes.
-
12
Pour sauce over noodle mixture and toss to combine.
-
13
Transfer to prepared baking dish.
-
14
Bake 20 to 30 minutes until top is nicely browned and casserole is bubbly.
-
15
Let cool slightly before serving.
