Heat a skillet or wok on medium-high heat and add 1 tsp oil and the seitan (I omit the oil entirely since I use a non-stick wok). Brown the seitan, then remove it from the skillet and set aside.
Add the rest of the oil to the skillet, then add the garlic and red Thai curry paste. Stir until mixed and cook for about 3 minutes, or until the garlic is fragrant.
Add the lime juice and zest and stir well. Add the green beans and toss to cover in the red curry paste.
Pour in the water, honey, and fish sauce (or vegan fish sauce). Cook until the green beans are tender, about 5-10 minutes.
Add the seitan and toss to cover in the sauce. Cook until the seitan have warmed through, about 2 minutes.
Remove from the heat and transfer to a serving bowl or plate and serve immediately.