To save time, I recommend store-bought rice noodles, preferably fresh. If you use dry noodles, you must soak them in water to soften up before use. To char the onion and ginger, heat the oven to 450 degrees C, and bake until brown. To toast the spices, add the spices to a dry pan over medium heat and keep tossing for an even toasting. Once the spices start to smoke, turn off the heat. Searing the ribs before adding to the vacuum bag will boost the flavor of the ribs due to the Maillard reaction, the stage where protein caramelizes. Although we start out with 6 liters of broth, as we cook it for 24 hours, the broth will reduce down to about 5 liters. If the broth is too reduced, feel free to add more water to maintain at least 5 liters of finished product. Pro tip: Once you’re comfortable with cooking pho, try adding more beef cuts, such as brisket, beef balls, tripe, tendon, etc. This will give your broth a much deeper and bolder flavor.