In a large sauce pot, bring 5 cups [8 cups] water to a boil. Stir in the ramen and cook until just tender, 3 to 4 minutes. Using tongs or a slotted spoon, transfer the ramen to a colander and rinse with cold water. Keep the cooking water at a simmer for the soup. While the water is heating and the ramen is cooking, prepare the ground meat.

• Peel and thinly slice the shallots. 
• Set aside half the tamari for serving. 
• Cut a small corner from the ground meat packaging and drain off any excess liquid. Transfer to a plate; pat dry with a paper towel. 

In a large frying pan over medium-high heat, warm 1 to 2 teaspoons oil until hot but not smoking. Add the shallots and cook, stirring occasionally, until starting to soften, 2 to 3 minutes. Add the ground meat, season with salt and pepper, and cook, stirring to break up the meat, until lightly browned but not yet cooked through, 3 to 4 minutes. 

Stir in half the tamari and cook until fragrant, about 30 seconds. Add ½ cup [1 cup] water and bring to a boil, then reduce to a simmer. Cook, stirring occasionally, until the meat is cooked through and the liquid has thickened, 2 to 4 minutes. Remove from the heat.

Return the ramen cooking water to a boil, stir in the arugula, and cook until just wilted, 1 to 2 minutes. Remove from the heat and stir in 1½ teaspoons [1 TBL] fish sauce. Add more fish sauce to taste and stir to incorporate. Meanwhile, prepare the garnishes.

• Coarsely chop the garlic. 
• Trim the root ends from the scallions; thinly slice the scallions. 
• Strip the cilantro leaves from the stems.

Transfer the ramen to individual bowls and ladle on the soup. Top with the meat and garnish with the garlic, scallions, and cilantro. Drizzle with the remaining tamari and serve.