The short answer is to invest in a Tuscan grill (see for a description). Build a roaring fire in your fireplace and let it burn down to embers. Rake the embers into a mound and place the Tuscan grill over them, then grill as you would outdoors.
To keep your fireplace from getting greasy, line it with aluminum foil (shiny side up to reflect the heat).
Indoor “Grills”
The advent of stovetop electric grills brought a traditionally outdoor cooking method into the kitchen. These grills feature an electric heating element positioned beneath a metal grate—a sort of inverted broiler. Indoor gas stovetop grills soon followed. But is this really grilling? In the case of an electric grill, a purist would say no. Indeed, the first qualification, live fire, is conspicuously absent. As for indoor gas grills, they function like outdoor models.
Both types of indoor grills offer the dry high-heat searing and charring so prized in outdoor grilling. I’m not sure that a blindfolded eater could tell the difference between outdoor and indoor grilled food that has been marinated well. And it certainly enables Frost Belters to enjoy grill-style food all year long.
Then there are skillet grills, frying pans with parallel raised ridges on the bottom that are designed to simulate grill marks. Here again, a purist might be tempted to dismiss these devices. Certainly there’s no live fire. But the ridges create the smoky charring and inviting grill marks so typical of grilling. Skillet grilling is no substitute for outdoor grilling, but it can serve the apartment dweller who wants to approximate a grilled flavor.