Step 1Place the sugar, corn syrup and one-half cup water in a heavy-bottomed saucepan and bring to a boil. Use a candy thermometer to watch the temperature and cook to 280 degrees, then carefully add the butter.
Step 2Bring the temperature to 330 degrees or until the mixture is amber. Remove from the heat and add the salt, vanilla extract and almond meal. Immediately pour onto a parchment-lined shallow pan to cool and set.
Step 1In a medium saucepan, bring the milk, cream, half the sugar and the ground coffee to a boil.
Step 2In a medium mixing bowl, use a whisk to combine the egg yolks and the remaining half cup of sugar and slowly -- so as not to cook the eggs -- pour it into the hot cream mixture.
Step 3Reduce the heat to low and stir until the mixture coats the back of a spoon, about 30 minutes. Strain the mixture quickly and chill in an ice bath, about 10 to 15 minutes.
Step 4Pour the mixture into an ice cream machine and follow the manufacturer's instructions. Remove from the machine and stir in the chopped toffee. Place the ice cream in a container with a lid, cover the surface of the ice cream with plastic wrap, cover tightly with the lid and freeze (several hours to overnight) to harden.
Step 1Mix 2 egg whites with the powdered sugar, almond flour and instant coffee and set aside.
Step 2Bring the granulated sugar and one-fourth cup water to a boil and, using a thermometer to monitor the temperature, cook until 240 to 248 degrees. Just before the sugar reaches temperature, begin beating the 2 remaining egg whites with a mixer. When the sugar syrup reaches temperature, turn the mixer on high and slowly add the syrup to the egg whites in a thin stream. Beat until the egg whites are firm and glossy.
Step 3Heat the oven to 350 degrees. Fold the meringue into the almond mix. Place macaron batter into a large pastry bag with a wide, straight opening.
Step 4With a marker, draw 2 1/2 -inch circles onto parchment paper cut to the size of your cookie sheet (you should be able to draw 4 to 6 circles per pan, with about 1 1/2 inches between each circle). Place the parchment face-down on the cookie sheet. Pipe the batter onto the parchment-lined cookie sheet. Shake the pan and tap lightly on the counter top until the meringue settles to about 3 1/4 inches in diameter, and let them sit 12 to 14 minutes to form a "skin" (the surface will have lost its sheen).
Step 5Bake about 10 minutes, until solid on the outside but still chewy in the center. Place cookies on a rack to cool. To store, leave on a rack in a cool, dry place for up to two days.
Step 6For ice cream sandwiches, place about half a cup ice cream between two macarons and press gently together.