My husband is Cajun and is very particular when it comes to crab cakes. He does NOT like filler, but it can be difficult to hold the cakes together without any. These are packed with crab, using only the smallest amount of breadcrumbs. Adjust the Tabasco to suit your tastes, then serve some on the side as well.
Break egg into a large bowl and beat with fork (or whisk).
Zest the lemon, then cut in half and squeeze to yield 1 tablespoon juice. Alternatively, use bottled lemon juice and skip the zest. Add lemon juice, zest, mayonnaise, mustard, horseradish, salt, red pepper flakes, Tabasco, and black pepper. Beat again.
Add crab, bread crumbs, parsley, and thyme. Stir well.
Form into patties (6 to 8), cover with plastic wrap, and refrigerate at least 30 minutes (longer is fine).
Melt butter in a large skillet (iron skillets work very well for this recipe) over medium heat. Cook crab cakes 3 to 5 minutes on each side, until browned and cooked through.
Serve with a dollop of mayo and a dash of Tabasco, or aioli.