Plastic waste is an ecological issue that triggered research and innovation (R&I) efforts for the delivery of bio-sourced and biodegradable alternatives. Because single use food packaging takes a significant share in the amount of generated plastic wastes, the EU commission funded an increasing number of projects on that topic within FP7 and H2020. This contribution presents R&D activities in the frame of two EU funded projects, EcoBioCap and YPACK, aiming at developing plastic food packages based on polyhydroxyalkanoates (PHA). These microbial polyesters do not need industrial composting facilities to degrade, but the bio-based and biodegradable benefits come at a cost: PHA are hard to convert into affordable and mechanically resistant thin films. Melt compounding PHA with other biodegradable polymers and natural fillers has been attempted in view to produce a cost-effective feedstock. However, the process lacked stability and 100 micron thick films showed poor tear resistance. Film blowing of a co-extruded PHA rich layer with a PHA poor layer was thus proposed to enhance both bubble stability and tear resistance. Here, the co-extrusion is detailed together with the different strategies developed to improve the adhesion between the layers and the relative PHA amount in films with thicknesses below 50 microns and elongation at break beyond 500%.