Place a medium skillet over medium-heat with 2 turns of the pan of olive oil, about 2 tablespoons. Add the sliced veggie sausage rounds and heat until brown and crispy, about 5 minutes. Remove from heat and reserve.

On the bottom of a ceramic casserole dish, place a layer of pretzel chips. Scatter a layer of sausage rounds over the pretzel chips, then sprinkle 1/4 cup of cheddar on top. Repeat each layer one more time, then pop the nachos in the oven until the cheese has melted, about 10 minutes. Remove nachos from the oven, drizzle with mustard and enjoy!