Run matzo under a tap of running water for 30 seconds. Alternatively, fill a large bowl or casserole dish with cold water and submerge the matzo crackers in it for 20-30 seconds (if using gluten-free matzo, 20 seconds are enough).

Break matzo into small pieces or about 1-2 inches. Transfer to a large bowl or casserole dish.

In a small bowl, beat eggs thoroughly. Add milk, salt and pepper, and mustard/ paprika (if using), and mix well to combine.

Pour the egg mixture on top of the matzo pieces. Mix well to combine.

Set a skillet to medium-high heat. Melt butter, Earth Balance, or olive oil.

OPTIONAL: If using onions, mushrooms, or any other mix-ins, add them to the skillet first and fry for 10 minutes, until the onions change colour (if using spinach, do not add it yet).

Add matzos and egg mixture to the pan, and mix well. Cook, stirring constantly, until the eggs are set, about 2-3 minutes (if using spinach, add along with egg mixture).

Taste and correct seasonings, topping with more salt and pepper to taste.

Serve matzo brei with your favorite toppings, like sour cream or apple sauce.