Heat oil in large Dutch oven over medium heat until shimmering. Add onion and cook, stirring frequently, until light golden, 8 to 10 minutes. Add garlic, ginger, chile, tomato paste, and garam masala; cook, stirring frequently, until fragrant, about 3 minutes. Add crushed tomatoes, sugar, and salt; bring to boil. Reduce heat to medium-low, cover, and simmer for 15 minutes, stirring occasionally. Stir in cream and return to simmer. Remove pan from heat and cover to keep warm.