Heat sufficient oil in a kadai. Drain moong dal and transfer it into a mixer jar. Add spinach, fennel seeds, cumin seeds, black peppercorns, ginger, green chillies, asafoetida, red chilli powder, turmeric powder, roasted cumin powder and grind into a coarse mixture. Transfer the mixture into a bowl. Add salt, besan, onion, lemon juice and mix well. 

Make small wadas of the mixture and slide into the hot oil. Deep fry the wadas till half done and drain on absorbent paper. Reheat the oil and deep fry the wadas till golden and crisp. Drain on absorbent paper. 

Sprinkle some chaat masala on the wadas.  Arrange spring onion greens and thin strips of red bell pepper on a serving plate. Transfer  the wadas onto the serving plate and serve hot.