Plant-based drinks (PBDs) as alternatives to milk is a fast-growing market in much of the western world, with the demand increasing every year. However, most PBDs from a single plant ingredient do not have an amino acid profile that matches human needs. Therefore, this study set out to combine plant ingredients to achieve a more balanced amino acid profile of novel plant drinks, by combining a high content of oat with the pulses pea (Pisum sativum) and lentil (Lens culinaris) in a solution. After removal of the sediment, the resulting plant drinks were composed of what could be kept in suspension. The amino acid and protein composition of the plant drinks were investigated with capillary electrophoresis, to identify the amino acids, and SDS-PAGE to assess the proteins present. The amino acid profile was compared against recommended daily intake (RDI). It was determined that the plant drinks with only oat and lentil did not have a strong amino acid profile, likely due to the higher pH of the lentil concentrate affecting which proteins could be kept in solution. Plant drinks with a combination of both lentil and pea, or only pea, added to the oat drink had an improved concentration of the amino acids that were otherwise in the low end compared to RDI. This includes a high content of phenylalanine, leucine and threonine, as well as a moderate amount of isoleucine, valine and methionine, and a contribution of histidine and lysine. An assessment of stability and sensory parameters was also conducted, concluding there was an advantage of combining oat with a legume, especially pea.