Place the steak on a plate and freeze for about 30 minutes until firm.
Meanwhile, whisk together the tomato juice, fish sauce, lime juice, oil, minced cilantro leaves and stems, sugar, Thai chile powder, and salt.
Slice the steak as thinly as possible — around 1/8-inch, then cut each slice into 1/8-inch batons. Next, using the sharpest chef’s knife you have, finely chop the batons. Gather the coarsely chopped meat and place it back on the plate, cover, refrigerate until ready to serve.
When ready to serve, whisk the sauce again then add 1/4 cup to the chopped meat and gently stir to combine. Taste and add more sauce as needed. Mold the tartare onto two serving plates, and drizzle with any extra sauce. Divide the peas between the two plates and garnish with mint and cilantro.