Matzah brei is comfort food, and amounts are all to taste. If you like your matzah brei more like scrambled eggs, use four eggs to two slices of matzah. If you like it more crunchy and less eggy, keep a one-to-one ratio. I love spicy foods, so I use two onions and eight ounces of kimchi, but if you don’t like super-spicy, cut back those amounts.