The present research focuses on studying teachers' beliefs about the complexity of learning the curricular languages in the Basque Country, with special focus on Basque, the minority language. The study adopts a mixed-methods research design. For the quantitative data, 1093 participants completed a specifically designed online questionnaire, which was administered to three groups: pre-service (N = 564), in-service (N = 418), and university teachers (N = 111). In the qualitative part of the study, the beliefs of 20 in-service teachers were collected through four focus groups. The results indicate that in-service and university teachers hold favourable beliefs toward learning curricular languages, and consider Basque a difficult language to learn, even more so than English and French. However, the statistical results suggest a significant change in that belief for the pre-service teachers, who perceive Basque easier to learn than English and French. This perception could result in the gradual elimination of the 'difficult language' label given to Basque. Moreover, in-service teachers show concerns about the imbalance between the knowledge of the minority language and the use. In particular, they seek innovative solutions for establishing Basque at the core of multilingual education, so that this minoritized language can take safe steps forward towards normalisation.