Salty brownie ice cream sandwiches

Preheat the oven to 325F with a rack in the center.

Line the 8x8 pan with heavy duty foil pressed carefully into the bottom, corners and sides without puncturing it; spray lightly with oil.

Combine the chocolate, butter and oil in a bowl and melt over a saucepan of about an inch of water on medium until smooth; set aside.

Whisk the eggs, sugar and vanilla until foamy, a little pale and slightly thickened.

Combine the chocolate mixture with the egg mixture, then add the flour and kosher salt.

Spread about half the batter evenly into the foil-lined pan to all corners, sprinkle with flaky salt, and bake about 9 minutes until matte, puffed in places and springy.

Cool a little, lift out with the foil, loosen the slab with a spatula and slide onto a cutting board.

Press the foil back into the pan, oil it again, spread the rest of the batter and bake the same, about nine minutes, with no flaky salt.

Crush the Oreos, leaving pieces big.

Loosen the second slab, invert it and return it to the pan as the base; freeze both slabs.

Cut the ice cream in its carton into pieces with a chef's knife; work it against the side of a large bowl until smooth and spreadable, then fold in the Oreos.

Spread the filling evenly over the base in the pan and freeze until set; the recipe says 45 minutes, about 15 was used here.

Press the salted slab on top, salt side up, and freeze until completely solid, at least an hour.

Lift out with the foil, peel it away, trim a thin strip from all four sides with a sharp chef's knife, then cut in half one way and into fourths the other.

Store in an airtight container in the freezer for weeks.