There are 25 bonus boards to break in the DLC. Below are timestamps for all of them:
00:00 - 1/25 (Nexus)
00:28 - 2/25 (Ice Cauldron)
00:47 - 3/25 (Ice Cauldron)
01:35 - 4/25 (Ice Cauldron)
01:48 - 5/25 (Ice Cauldron)
03:20 - 6/25 (Ice Cauldron)
03:43 - 7/25 (Ice Cauldron)
04:30 - 8/25 (Ice Cauldron)
04:59 - 9/25 (Ice Cauldron)
05:28 - 10/25 (Ice Cauldron)
06:18 - 11/25 (Giant's Canyon)
07:00 - 12/25 & 13/25 (Giant's Canyon)
07:53 - 14/25 (Giant's Canyon)
08:36 - 15/25 (Giant's Canyon)
09:26 - 16/25 (Giant's Canyon)
10:31 - 17/25 & 18/25 (Forest Falls)
12:16 - 19/25 (Forest Falls)
13:04 - 20/25 (Forest Falls)
13:44 - 21/25 & 22/25 (Forest Falls)
14:47 - 23/25 (Forest Falls)
16:07 - 24/25 & 25/25 (Forest Falls)