In heavy bottom frying pan heat 2 teaspoons of oil and stir-fry cabbage and bell pepper for about 2 minutes, they should be still crispy. Sat aside.
Wash the Bengal gram changing water 3-4 times, and soak them in 3 cups of water for at least three hours. Cook them in 2 cups of water until kala chana is soft and tender, after it comes to boil it should take about 20 minutes. Notes: Cook them without salt whole lentils cook faster without salt.
Drain the remaining water.
Grind the Bengal gram (without adding any water), ginger and green chili in food processor. This will become grainy and thick dry mix.
Remove from food processor and add potato, cilantro, fennel, coriander, red chili powder, mango powder, garam masala, salt and lemon juice, mix it well. If it is too dry add little water as needed. Divide them in six equal parts and make them in thick patty.
Heat the skillet over medium heat, grease the skillet generously and put the petties over. Grease the patties from the top and grill from both sides until they golden brown. It should take about 8 minutes.
Next grill the buns lightly butter.
Assemble the vegetable burger one side of the bun spread the cilantro chutney put petty over, put some grilled veggies and drizzle the tamarind chutney.
Delicious veggie burger is ready to serve.