diff --git a/pspipe_utils/simulation.py b/pspipe_utils/simulation.py
index 622a2ca..dbeaa71 100644
--- a/pspipe_utils/simulation.py
+++ b/pspipe_utils/simulation.py
@@ -3,6 +3,7 @@
 """
 import numpy as np
 from pixell import curvedsky
+from mnms import utils
 from pspy import so_spectra
 
 
@@ -114,7 +115,8 @@ def foreground_matrix_from_files(f_name_tmp, arrays_list, lmax, spectra, input_t
     return l, fl_array
 
 
-def generate_fg_alms(fg_mat, arrays_list, lmax, dtype="complex64"):
+def generate_fg_alms(fg_mat, arrays_list, lmax, dtype="complex64",
+                     method='mnms', **method_kwargs):
     """
     This function generate the alms corresponding to a fg matrix
     the alms are returned in the form of a dict with key "freq"
@@ -134,7 +136,12 @@ def generate_fg_alms(fg_mat, arrays_list, lmax, dtype="complex64"):
 
     narrays = len(arrays_list)
 
-    fglms_all = curvedsky.rand_alm(fg_mat, lmax=lmax, dtype=dtype)
+    if method == 'mnms':
+        func = utils.rand_alm
+    elif method == 'curvedsky':
+        func = curvedsky.rand_alm
+
+    fglms_all = func(fg_mat, lmax=lmax, dtype=dtype, **method_kwargs)
     fglm_dict = {}
     for i, array in enumerate(arrays_list):
         fglm_dict[array] = [fglms_all[i + k * narrays] for k in range(3)]