Line a dinner plate with paper towels and place block of tofu on top. Add another layer of paper towels on top of tofu and top with another dinner plate. Set aside in the refrigerator for 30-45 minutes.
Cut drained tofu into approx. 1/2" cubes.
Whisk together all marinade ingredients. Pour half over sliced tofu and toss gently to coat. Set aside remaining marinade.
Heat a large skillet or wok over high heat, then add olive oil and swirl around the pan. Add vegetables and toss to stir-fry for 4-5 minutes or until tender-crisp. Set aside on a baking sheet or large plate.
Add tofu to the hot skillet or wok, tossing to sear all sides until lightly browned (5-6 minutes). Add the remaining marinade.
As the tofu continues to cook, whisk arrowroot flour into 2 tbsp of water. Add mixture to wok or skillet and gently mix. Bring to a boil, then return veggies to the wok and toss until evenly coated.
Serve with rice.