A decolonising mind-set holds the following things as essential:
1: The modern world we live in was built on the basis of the exploitation and enslavement of African, Asian, American and Australasian peoples by Europeans. Colonialism coincided with the development of capitalism, modern economic thought and global financial and state frameworks.
2: In order to successfully exploit these peoples, colonial states developed racism and concepts of racial superiority, which are specific types of bigotry, as justification for this exploitation.
3: The modern globalised economic and political system is built on a colonial and racist legacy and, while some of it has been undone, much (arguably most) of it has not.
4: The colonial and racist systems serve to render invisible the lives and voices of the global majority who are not European/of European descent.
5: A decolonising mind-set rejects the silencing of non-European voices, rejects racist structures, and seeks to redress this imbalance by reframing issues around the experiences of peoples who have traditionally been rendered invisible.
A resource on decolonising economics education: http://www.rethinkeconomics.org/journal/lets-decolonise-economics-education/