In medium bowl, mix together masa harina and 3/4 teaspoon salt and 1 cup plus 2 tablespoons hot tap water. Cover with plastic wrap and let rest while preparing beans and chorizo. In a food processor, process beans until completely smooth. Stir in a little water, if necessary, to make them spreadable (but still quite thick). Scoop chorizo into medium skillet. Set over medium heat. Cook - stir regularly to break up clumps - about 4 minutes, until thoroughly cooked. If there is lots of rendered fat, tip off excess and discard. Set aside.
Heat a well-seasoned or nonstick griddle or heavy skillet over medium. If necessary, knead a few drops of water into the masa to give it the consistency of soft cookie dough. Divide into 8 portions; cover with plastic. One by one, form huaraches: Line tortilla press with two pieces of plastic cut to fit plates (cut from a food storage bag - thicker plastic works better for beginners). Roll a portion of masa into egg shape, press thumb into middle to make long, deep, wide hole. Spoon in 2 scant teaspoons beans, (masa will look like a canoe when the hole is the right size to fit the beans). Pinch dough up around the beans to completely enclose. Gently roll into a cigar shape about 5 inches long.
Using tortilla press, gently press out between sheets of plastic - perpendicular to handle of press - into 6-inch oval. Peel off top sheet of plastic. Flip - uncovered side down - onto the fingers of one hand and gently peel off second piece of plastic. In one flowing movement, roll huarache off hand and onto griddle or skillet. After about 1 minute, flip and bake for another 2 minutes until lightly browned. Remove to a plate and cover lightly with plastic.
Set out the tomatillo (or other) salsa, grated cheese and radishes. Pour enough oil onto your griddle or skillet to coat heavily. Set over medium to medium-high heat. When quite hot, lay on as many huaraches as will fit in a single layer. When crisp underneath - 1 1/2 minutes - flip over. Spread each with about 1 1/2 tablespoons salsa, sprinkle on a little chorizo and dust with cheese. Let crisp underneath for a minute or two, then slide onto a serving platter or individual plates and decorate with the radishes. (If working in batches, go ahead and serve first finished huaraches while you finish the remainder.) Pass the extra salsa for your guests to add as they wish.