Add the walnuts to the jar of a food processor and pulse a few times until they are ground, being careful not to turn them into butter.

Transfer the ground walnuts to a saucepan and add the sweet condensed milk, stirring until combined. Bring it to the stove, over medium low heat, and cook - stirring constantly - until thickened and releasing from the bottom of the pan when you run the spoon from side to side. That should take about 10 minutes.

Transfer to a greased plate, cover with plastic film and let it cool to room temperature, preferably overnight.

Use a little butter to grease your hands and take about a tablespoon of the mixture to form into an oval shape roll. Repeat with the remaining mixture and reserve.

In a double-boiler, combine the confectioner's sugar with the lime juice and start adding the milk, a little at a time, whisking firmly until the sugar has melted and you achieve a paste consistency. It should be thick and creamy and not runny, so you might not need all the milk. (See notes.)

Using a fork, dip each camafeu into the glaze, letting the excess drip off.

Transfer the glazed camafeus to a parchment paper covered plate and decorate each with a walnut. Allow them to dry completely before trimming off excess glaze with a knife and transferring them to bonbon cups!