<span th:text="${@myBean.doSomething()}">

<span th:text="${myBean.doSomething()}">

@Configuration
@EnableWebMvc
@EnableSpringDataWebSupport
public class MyWebConfig extends WebMvcConfigurerAdapter {
[....]
public ClassLoaderTemplateResolver emailTemplateResolver() {
    ClassLoaderTemplateResolver resolver = new ClassLoaderTemplateResolver();
    resolver.setPrefix("emailtemplates/");
    resolver.setSuffix(".html");
    resolver.setCharacterEncoding("UTF-8");
    resolver.setTemplateMode("HTML5");
    return resolver;
}

@Bean
public SpringTemplateEngine emailTemplateEngine() {
    SpringTemplateEngine engine = new SpringTemplateEngine();
    engine.addTemplateResolver(emailTemplateResolver());
    engine.addDialect(new LayoutDialect()); // thymeleaf-layout-dialect
    addSpringSecurityDialect(engine); // thymeleaf-SpringSecurity-dialect
    return engine;
}
[....]
}

@Service
public class MyEmailService {
@Resource SpringTemplateEngine emailTemplateEngine;
[....]
public boolean sendHtmlEmail(...) {
    final Context ctx = new Context(locale);
    ctx.setVariable("someVariable", "someValue"); // Don't want to add myBean here
    final String body = this.emailTemplateEngine.process("myTemplate", ctx);
    [....]

@Component
public class MyBean {
    public String doSomething() {
        return "Something done!";
    }
}

<span th:text="${@myBean.doSomething()}">