In a large mixing bowl, whisk together rice flour, lentil flour and 2 ½ cups water.
Cover and let rest for at least 8 hours.
Before using, stir in the salt.
Heat a nonstick crepe pan over medium to medium-high heat.
In a circular motion, pour just less than ½ cup of the batter onto the crepe pan. Immediately use the back of a ladle to gently spread the batter. If the batter does not spread easily, you may need to add additional water to the batter. If not using a nonstick pan, first brush canola oil on the pan or coat it with cooking spray (repeat for each crepe).
Cook until the edges are set and the crepe is turning golden brown on the bottom, about 2 minutes.
Using a spatula, carefully flip the crepe. Cook for 1 minute. Transfer the crepe to a plate.
Repeat with the remaining batter, separating the finished crepes with wax paper or parchment paper.