This Asian and Cajun-influenced shrimp sandwich is simple to make and bursting with flavor. Try it in a lettuce cup for a lighter lunch. If you can't find lemongrass you can use zest of lemon instead.
Heat a grill pan or skillet over medium-high heat. Working with a few pieces at a time, cook the bread until browned and toasted 2 to 3 minutes. (Alternatively, heat the oven to broil and broil the bread until toasted, about 2 minutes, depending on the strength of your broiler.) Set aside and keep warm.
Place the shrimp in a bowl. Add the Creole seasoning and toss to coat. Melt the butter in a large skillet over medium-low heat. Add the garlic, jalapeno, ginger, and lemongrass. Cook until fragrant, 45 to 60 seconds. Add the shrimp and increase the heat to medium-high. Add the lemon juice, hot sauce, and fish sauce. Cook, turning once or twice, until the shrimp are firm and pink, 1 to 2 minutes per side. Taste and adjust for seasoning with salt and pepper.
Spoon the shrimp and juices atop the grilled bread. Serve immediately, with lots of napkins!