Quickly rinse the mushrooms and dry them with a paper towel. I like to remove the bottom of the stem which is frequently dirty and sometimes a bit woody. Second, chop the mushrooms into 2 to 4 pieces depending on the size.
Rinse the green onions. After you rinse them shake them out to get rid of the excessive water or use a paper towel to dry them out. Further, grab the entire bunch and start to cut the onions finely in circles. Rinse and chop the cilantro finely and set aside.
When you are ready to cook in a heavy-bottom skillet on medium heat, add in unsalted butter and oil. Second, add in cumin seeds. Third when the cumin seeds sizzle add in minced garlic. Further let it cook for a minute until fragrant. Stir.
Add in red chili powder, crushed red pepper, chaat masala, salt, and stir well. Furthermore, add in mushrooms. Then add in 2 tablespoons water and let them cook for 3 to 4 minutes. Then add the green onions. Let them sauté for 2 minutes until the water has evaporated. Finally, top with cilantro and lemon juice.