Grind about ½ cup freeze dried raspberries in a food processor or blender. Ensure you have 3 tablespoons of powder and add it to a jar with ½ cup of water. Seal the jar and shake it to mix. Let sit for at least an hour or up to 4. This dissolves the powder into the water.
After an hour or so, pour the raspberry water through a fine mesh sieve into a ⅓ cup measuring cup - pressing the seeds through to get every last drop. It should nearly fill the cup, add some water to get the liquid to fill the cup.
Pour into a small pot and add the sugar. Stir then turn the heat to medium low. Keep a thermometer nearby.
Add the egg whites to the bowl of a stand mixer and attach the whisk. Begin whisking until the eggs are a bit frothy, they should still be liquid on the bottom but there will be bubbles on top.
Cook the sugar & raspberry mix until a thermometer reads 245 F. Once it does, turn off the heat and set the pan off the heat for just a minute.
Turn the mixer on again and pour the liquid, slowly over the egg whites as they whip. Scrape down the bowl and then turn the mixer onto medium high. Whip - adding the pinch of salt and a dash of vanilla as you do - until you have a thick, glossy meringue that holds shape when you turn the whisk upside down.
Spread the meringue over the curd. You can set it in the fridge until it's time to serve.
Right before serving, toast the meringue with a kitchen torch, get it nicely browned all over.
To serve, run a chef’s knife under hot water until it’s warm. Wipe it dry then slice the bars.