Prepare the ravioli according to package directions.
Meanwhile, melt the butter in a non-stick skillet over medium heat. Continue to cook the butter, swirling the skillet until it is starting to form browned bits in the bottom of the skillet.
Add the peanut butter and red curry paste to the skillet and whisk until smooth.
Remove the sauce from the heat and whisk in the lime juice, sugar and salt. Taste the sauce and add more curry paste if you like more heat.
Return the sauce in the skillet to the stove over low heat. Stir the pumpkin ravioli into the sauce until it is well coated. Serve.