3 tbsp extra-virgin olive oil
coarse salt et freshly ground pepper
1 1/2 lbs ground beef
8 ozs cremini mushrooms, sliced, 3 cups
1 large onion, chopped, 2cups
1/2 cup pilsner-style beer
2 tsps dijon mustard
2 tsps cornstarch
1 1/4 cups chicken broth
1. preheat over to 425. cover potatoes w/2 ins water in a pot; bring to a simmercook until tender, 17mins. drain et return to pot. mash w/2tbsps oil; season w/salt.
2. place beef in a 10-in cast-iron skillet over med-high et cook, stirring occasionally et breaking up large pieces w/ a spoon, until browned, 11mins. transfer to a plate using a slotted spoon; pour off excess fat in skillet.
3. add tbsp oil. mushrooms, et onion to skillet; cook stirring occasionally, until browned, 6mins. add beer; cook until reduced, 3mins. whisk together cornstarch, mustard, et broth in a bowl; add to skillet et bring to a boil. return beef to skillet; season w/salt et pepper. top w/mashed potatoes. bake until bubbling, 30mins. serve hot.