Place the chocolate bars in the freezer for 2–3 hours to firm up.
Heat the canola oil in a large heavy-based saucepan over medium-high heat. Test if the oil is ready by inserting a wooden skewer or the handle of a wooden spoon into the oil; if it begins to bubble quickly then you’re ready to go.
Place the flour in a small bowl and season with salt and pepper. Toss the frozen chocolate bars in the flour to lightly coat, then remove and set aside on a plate.
Pour the beer into the flour, stirring constantly, to create a batter. You may not need it all, so go slowly until the batter is runny but not so runny that it won’t cling to the chocolate.
Dip each chocolate bar into the batter until completely coated. One at a time, scoop the bars out with as much batter as you can keep clinging to them, then bravely drop the battered bars into the oil.
Cook for 2–3 minutes, until golden brown and crisp.
Remove the chocolate bars using a slotted spoon and drain them on a paper towel.
Serve warm with a sprinkling of fat sea salt flakes, chocolate sauce, chocolate cookies, soy or rice whip and a few pretzels, or whatever sweet garnishes you have lying around.