In a large bowl, combine yogurt, 2 teaspoons garam masala, salt, lemon juice, cumin, 1 teaspoon ginger, and tempeh.
Add tempeh, peas, 3 more teaspoons garam masala, turmeric, 1 more teaspoon ginger, tomato sauce, whipping cream, and brown sugar.
Remove from heat and stir in cilantro, if using.
Let the sauce cool and then add to a gallon freezer bag.
Add contents of the bag to a large saucepan and cook over medium heat, covered, for 20 minutes.
Serve over brown rice or any other starch.
I added 1 1/2 cups of spinach to the sauce while I was reheating. It not only made the dish healthier, but also helped to add a bit more liquid to the saucepan.
You may need to add more water to the saucepan if the frozen meal has a hard time thawing.