diff --git a/ecc/bls12-377/fr/sis/sis.go b/ecc/bls12-377/fr/sis/sis.go
index dcd2c15b9..93c461c4f 100644
--- a/ecc/bls12-377/fr/sis/sis.go
+++ b/ecc/bls12-377/fr/sis/sis.go
@@ -108,14 +108,8 @@ func NewRSis(seed int64, logTwoDegree, logTwoBound, maxNbElementsToHash int) (*R
 			partialFFT_64[mask](k, twiddlesCoset)
 		}
 	} else {
-		cosetTable, err := r.Domain.CosetTable()
-		if err != nil {
-			return nil, err
-		}
-
 		r.smallFFT = func(k fr.Vector, _ uint64) {
-			k.Mul(k, fr.Vector(cosetTable))
-			r.Domain.FFT(k, fft.DIF)
+			r.Domain.FFT(k, fft.DIF, fft.OnCoset(), fft.WithNbTasks(1))
 		}
 	}
 
diff --git a/field/generator/internal/templates/sis/sis.go.tmpl b/field/generator/internal/templates/sis/sis.go.tmpl
index 79ecb0b08..53271d721 100644
--- a/field/generator/internal/templates/sis/sis.go.tmpl
+++ b/field/generator/internal/templates/sis/sis.go.tmpl
@@ -113,14 +113,8 @@ func NewRSis(seed int64, logTwoDegree, logTwoBound, maxNbElementsToHash int) (*R
 				partialFFT_64[mask](k, twiddlesCoset)
 			}
 		} else {
-			cosetTable, err := r.Domain.CosetTable()
-			if err != nil {
-				return nil, err
-			}
-			
-			r.smallFFT = func(k {{ .FF }}.Vector, _ uint64) {
-				k.Mul(k, {{.FF}}.Vector(cosetTable))
-				r.Domain.FFT(k, fft.DIF)
+			r.smallFFT = func(k fr.Vector, _ uint64) {
+				r.Domain.FFT(k, fft.DIF, fft.OnCoset(), fft.WithNbTasks(1))
 			}
 		}
 	{{- end}}