Wrap tofu in a clean dish towel and weight it with something heavy, such as a large can; leave it to drain for 30 minutes.
Slice tofu crosswise into 12 skinny slices, then cut those in half so you end up with 24 skinny half slices.
Mix maple syrup, soy sauce, and lemon juice together in a bowl.
Heat oil in a large nonstick skillet over medium heat. Arrange tofu in a single layer in skillet and cook, undisturbed, until golden and crisp on bottom, 5 to 7 minutes. (It won't get very dark, but it will look nice and appetizing.) Turn all pieces over and cook another 3 to 4 minutes. Reduce heat to low, add garlic and cook, moving garlic around with a spatula in spaces between tofu, 1 minute.
Increase heat to medium-low. Add maple syrup, soy sauce, and lemon juice, shaking to distribute sauce. Cook a minute or so, then turn and cook another minute or so, until sauce is reduced to a syrupy glaze and tofu looks nicely coated. Transfer tofu to plates and scatter with chives or scallions.
