Make sure the bottom of the bowl isn’t touching the simmering water.

Transfer mixture to the bowl of a stand mixer.

Start folding gently forming a letter J with a spatula. Add the food coloring at this point, if using.

Test again.

You don’t want your batter to be too runny either. So be careful not to overmix. It’s always best to undermix and test several times until the proper consistency has been achieved.

Bake one tray at a time.

Remove from the oven and bake the other tray.

Let the macarons cool down before proceeding with the filling.

Place brown sugar and balsamic vinegar in a small saucepan. Bring to a gentle boil.

Let mixture simmer over medium heat for about 3 minutes, until thickened and reduced.

Add heavy cream.

Be aware that the mixture will probably splash once you do this.

Bring it back to a boil, and simmer again over medium heat for another 2-4 minutes, until thick.

Add butter and salt. Mix to combine, until butter is melted.

Remove and transfer to a bowl. Let it cool down completely before adding to the Swiss meringue buttercream.

Remove butter from the fridge about 30 minutes before you start to make this. We are looking for the perfect butter temperature and consistency. It shouldn’t be hard cold, and it shouldn’t be so soft that is almost melting.

Put whites and sugar in a heatproof bowl.

Place bowl on top of a small pot with simmering water.

Once you achieve that temperature, transfer the syrup to your mixer bowl.

Test every so often, so you don’t over whip it.

Start adding the butter that should be slightly softened.

Cut butter into very thin pats. Starts doing one by one with mixer running on medium-high.

Wait for one butter pat to be incorporated before adding the next one.

This whole process could take about 15 minutes. Add vanilla extract.

Once butter is all incorporated add 1/4 cup of the Balsamic Caramel Sauce to the Swiss Meringue Buttercream. The caramel sauce should be at room temperature.

You might have leftover buttercream from the macarons. I wouldn't advise halving the formula. Simply store leftovers in the fridge for up to 4 days, or in the freezer, for up to 2 months. Remember to package it really well in sealed air tight containers, or zip loc bags, before freezing.

To use it again, simply let it thaw until it comes to room temperature and beat it briefly to make it creamy again before using.

Mix cornstarch and cold water in a small bowl.

Once strawberries have boiled and reduced a bit, add cornstarch and water to the pan.

Bring back to a boil, stirring constantly, until mixture is thickened.

Let jam cool. Cover it with plastic wrap and place it in the fridge.

You may process the jam in a small food processor to make it smooth if you want to, which will help with filling the macarons, since you will only need a tiny bit for each macaron, and you don’t want to have huge chunks of strawberries in there.

Pipe a ring of Balsamic Caramel Swiss Meringue Buttercream around the edges of the bottom shells.

Spoon some strawberry jam in the middle.

Top with another shell.

Drizzle some caramel on top.

Top with salt if desired.

Store macarons in the fridge for up to 5 days.

I don’t usually recommend freezing macarons with jam fillings, because they can become soggy. But if you choose to freeze them, do so in an air tight container for 1-2 months.