Lenses uses Kafka consumers and producers. The prefix lenses.kafka.settings.client can be used to set properties.

lenses.kafka.brokersA list of host/port pairs to use for establishing the initial connection to the Kafka cluster. Add a few broker addresses here and Lenses will bootstrap and discover the full cluster membership (which may change dynamically).stringyes
lenses.kafka.settings.client.security.protocolProtocol, PLAINTEXT, SSL, SASL_SSL, PLAINTEXT_SASLstringyes
lenses.kafka.settings.client.ssl.truststore.locationPath to the truststorestringno
lenses.kafka.settings.client.ssl.truststore.passwordPassword for the truststorestringno
lenses.kafka.settings.client.ssl.keystore.locationPath to the keystorestringno
lenses.kafka.settings.client.ssl.keystore.passwordPassword for the keystorestringno
lenses.kafka.settings.client.ssl.key.passwordKey passwordstringno

Broker Metrics 

lenses.kafka.metrics.sslFlag for if SSL is enabledbooleanno
lenses.kafka.metrics.userUser name if securestringno
lenses.kafka.metrics.passwordPassword if securestringno
lenses.kafka.metrics.typeJMX type, JMX, JOLOKIAG, or JOLOKIAP.
JMX - Java Management Extensions is more common
Jolokia supports two APIs a GET and a POST based one.
Use JOLOKIAG if the metrics are exposed via GET requests.
Use JOLOKIAP if the metrics are exposed via POST requests.