2tsp.arrowroot powder (for runnier curd) OR 1 tbsp. arrowroot for thicker curd
Put the juice in a small pot and set it on the stove over low heat to medium heat.
While it warms up, combine all other ingredients in a medium-sized mixing bowl. Whisk until you have a smooth mixture with no lumps.
One the lemon juice is warm (not hot!!!), test it with your finger. You want it to feel warm to the touch, but not burn you. If it's too hot (please don't hurt yourself!), let it cool a bit. You want it warm, but not so hot that it will cook the eggs. Warm to the touch, but nothing that hurts or will burn you.
A little drizzle at a time, whisk the warm lemon juice into the egg mixture. Keep whisking until all the juice is incorporated.
Return the entire batch of batter to the pot and heat over medium heat, whisking at a medium pace consistently. The trick to a good curd or custard is continuous stirring. Not fast like scrambling eggs, but not so slow that things bubble or boil. Just a medium pace that remains continuous the entire time.
Continue stirring until the sauce thickens (about 3-5 minutes)
Once thickened, pour the lemon curd into a heat and food-safe container and cool in the fridge.
Keep in fridge and use on low carb toast in the morning or simply as a decadent dessert on it's own.