If you have time, soak chana dal for 30 minutes. This will expedite the cooking process. Otherwise, simply rinse and drain the lentils.Combine lentils with water in a medium size sauce pan. Bring to a boil on high flame. Lower the heat and simmer the lentils until they are very tender but not mushy. Drain and reserve the cooking liquid. Spread the cooked dal on a wide plate and let cool completely.
Once cooled, grind to a smooth powder along with ground cumin and salt. Divide the mixture into small lemon size balls, about 12~15. Set aside.
Prep the Dough:
While the lentils are cooling, make the dough. In a mixing bowl, combine the flour, salt and turmeric. Add the reserved dal cooking water and oil. Mix and knead until a soft, pliable dough forms. Add more water, if needed. Cover and set aside for 15~20 minutes.
Make Dhal Puri:
Divide the dough into 12~15 equal size pieces. Flatten them out into a flat disc and make a depression in the middle. Place the dough ball in the depression and bring the dough ends over the filling encasing it. Gently flatten it. Repeat with the remaining dough and filling. Coat the stuffed dough with flour to avoid sticking together. On a lightly floured work surface, roll each stuffed dough ball into a thin roti - the thinner the better.
Place the stuffed roti on a preheated griddle or tawa. Cook on medium-high flame until lightly golden and tiny brown spots form on both sides. Brush with oil while cooking. Repeat with the remaining dough and dal filling.
Soaking the split pea lentils for about 30 minutes expedites the cooking process.
I usually add about 1 cup of whole-wheat flour or atta to 2 cups of all purpose flour to make dholl puri. This adds some fiber and nutrition to the flatbread.
Add a pinch of red chili powder or ground pepper to add spice to the filling.
Make sure that the lentils are completely cooled before blending. If not, the mixture might become pasty instead of a powder. This will make stuffing dholl puri difficult. So, take your time and allow the lentils to cool.
If you are in a hurry to cool the lentils, then spread them out on a kitchen towel and place a small fan next to it.
Try to roll the flatbread as thin as possible for the best texture.
Dholl puri taste perfect when served warm or at room temperature. If you have any leftovers, then let them cool completely before wrapping them in foil. Then store them in the fridge for up to 2 days or freeze them for up to 1 month.
To reheat, wrap the flatbread in damp paper-towel and microwave until heated through.