Stir together the cream, milk, ¼ cup sugar, coffee and salt in a medium saucepan. Place over medium-high heat. When the mixture just begins to bubble around the edges, remove from heat and cover. Let steep for about 10 minutes, stirring occasionally, until the cream has a strong coffee flavor.

In a medium bowl, whisk together the egg yolks and remaining ¼ cup sugar. Uncover the cream mixture and return to medium heat.

Whisking constantly, gradually pour about 1 cup of the warm cream mixture into the egg yolk mixture. Pour the mixture back into the saucepan and cook over medium heat, stirring constantly and scraping the bottom, until the mixture is thick enough to coat the back of a spoon or spatula.

Pour the mixture through a fine mesh strainer set over a medium bowl, preferably one with a pour spout. Cover with plastic wrap and refrigerate until well chilled.

Freeze in an ice cream maker according to manufacturer’s directions. While the ice cream is churning, place your storage container in the freezer. In the last couple minutes of churning, add in the chopped toffee, or quickly stir it in as you transfer the ice cream from the maker to the storage container. Cover and freeze until firm, about 4 hours.