Currently, the shift to a greener economy requires the prospection of new industrial processes to reduce greenhouse-gas emissions. Enzymatic catalysis is considered a green alternative to traditional industrial processes. Among enzymes of industrial relevance, starch-degrading enzymes, such as α-amylases, have received attention because of their enormous potential to hydrolyze starch-based materials, generating smaller sugars that can be used for the biosynthesis of chemicals of industrial relevance, such as ethanol. In the present study, a new isolate of Paenibacillus barengoltzii was obtained from cow rumen and its potential to produce amylases was evaluated. Additionally, a recombinant amylase, AmyPb, was produced and biochemically characterized. AmyPb displays high activity at elevated temperatures (55 °C) and can withstand elevated temperatures. The experimentally calculated melting temperature showed that AmyPb is more stable in alkaline environments, with a Tm of 59 °C at pH 9. AmyPb hydrolyzed potato and cassava starches with hydrolysis efficiencies of 28 and 55%, respectively. The results of this study are relevant for the development of industrial processes that employ thermostable amylases.