Step 1 - Soak the Mung Beans (The Night Before)
Rinse the split mung beans thoroughly under cold water, then add them to a large mixing bowl. Cover with lukewarm water use at least twice the volume of water to beans, as they absorb a significant amount. Cover the bowl and leave to soak for at least 6 hours at room temperature, or refrigerate overnight.
Don't rush this step. Under-soaked mung beans don't blend smoothly and the batter ends up grainy and uneven. Six hours is the minimum; eight hours overnight is better.
Step 2 - Preheat and Blend the Batter
Preheat your oven to 375°F (190°C). Drain the soaked mung beans and rinse well under cold water.
Add the drained beans to your high-speed blender. Add the black salt, onion powder, turmeric, coconut milk, olive oil, chickpea flour, and baking powder. Blend on high for 60–90 seconds until the batter is completely smooth, creamy, and uniformly yellow. No chunks, no graininess smooth enough that it pours freely.
Taste the batter at this point. It should taste savory, slightly eggy from the black salt, and mildly spiced. Adjust: more black salt for stronger egg flavor, more turmeric for color, more chickpea flour if too thin, more coconut milk if too thick.
Step 3 - Heat the Skillet
Place your 12-inch oven-safe cast iron skillet on the stovetop over medium heat. Add enough olive oil to coat the entire surface tilt the pan to spread it evenly up the sides too. Let the skillet get properly hot before adding any batter. A hot skillet sets the bottom of the frittata immediately, which prevents sticking and creates that golden-brown base.
Step 4 - Add the Batter and Toppings
Pour the batter into the hot skillet in one smooth pour. It will sizzle slightly at the edges that's correct. Immediately scatter your vegetables across the top. Arrange them deliberately rather than randomly the frittata is going to look exactly like what you put on top. Add spoonfuls of vegan parmesan if using.
Move quickly at this stage. The batter starts setting from the bottom the moment it hits the hot skillet, so you have about 60 seconds to arrange your toppings before the surface starts to firm.
Step 5 - Transfer to the Oven and Bake
Slide the skillet directly into the preheated oven immediately don't wait. Bake uncovered for 10–15 minutes, checking at the 10-minute mark. The frittata is done when the edges look completely dry and slightly pulled away from the sides of the skillet, and the center no longer jiggles when you gently shake the pan.
Don't overbake. An overbaked frittata becomes rubbery and dry pull it when the center just barely sets. It continues cooking slightly from residual heat after you remove it from the oven.