Heat the olive oil in the pressure cooker and brown the garlic. Add the split peas, turmeric, garam masala and curry powder and stir well.
Add the tomatoes with their juice and the water and seal the cooker. Cook 18 minutes from when it reaches pressure.
Turn off heat and release steam. Season with salt and pepper. Remove two small ladles of the split peas. Blend the remainder until smooth, then add the reserved split peas and serve.