If using French toast, slice into 3/4th inch thick pieces. Slice each piece into 2-3 thick "sticks." If using Texas toast, cut each piece into 3-4 "sticks."
In a large bowl, briskly whisk the 4 eggs. Pour in the milk, brown sugar, vanilla extract, and pinch of salt. Whisk to combine.
In a blender or food processor, add the cereal and pulse until it forms crumbs.
Dredge each French toast stick in the egg + milk mixture and then generously coat with cereal crumbs. Repeat until all of the bread is coated. Depending on how generously you dredge the sticks into the cereal crumbs, you may need to pulse another 1/2 to full 1 cup.
Place a large nonstick skillet over medium-low heat and add a pat of butter. Once the butter has melted, add in 5 french toast sticks into a single layer in the pan. (Don't over-crowd.) Cook the sticks until they are crispy and golden brown and then flip to the other side. Once that side is crispy, get the sides and then transfer to a plate.
Cook the rest using the same method (adding a pat of butter, putting down 5 sticks, cook and flip) and then serve immediately with a dust of powdered sugar, fresh berries, and maple syrup as desired.