Vegan Chickpea Tuna Casserole

For the casserole

• 3 cups 280 g/10 oz bowtie noodles
• 1 cup 250 mL/150 g frozen peas

For the Roux

• 2-3 tbsp vegan butter or neutral flavoured vegetable oil
• 1 small onion ~100 g/4 oz, diced
• 2 ribs 90 g/3 oz celery, diced
• 1/4 cup 40 g/1.5 oz all purpose flour (can sub tapioca or cornstarch)
• 1 1/2 cups 375 mL broth (or pasta water + bouillon)
• 1 tbsp 15 mL mushroom broth powder (you can omit if using seasoned broth or bouillon)
• 3 tbsp 45 mL nutritional yeast
• 1 tsp 5 mL Old Bay Seasoning (can just add whatever spices/herbs you have if you don't have this)
• 2 tbsp nori cut into small slivers
• 1 cup 100 g/6 oz vegan cheese
• 2 cups 500 mL soy milk (can sub any milk alternative)
• 1/2 tsp 2.5 mL kosher salt (you can add more, the sauce needs to be salty enough to carry the pasta)
• 2 cups 310 g/11 oz cooked chickpeas
• 1/2 a sleeve of saltines for the crust I also like panko crumbs or potato chips!