In Vue CLI, Instant prototyping is known as rapid prototyping with just a single *.vue file with the vue serve(similar to vue create) and vue build commands. But you need to install below global addon for this.
npm install -g @vue/cli-service-global
yarn global add @vue/cli-service-global
You can also provide entry component for vue serve and target file for vue build using below commands
vue serve MyComponent.vue
vue build MyComponent.vue